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URL https://opencores.org/ocsvn/rio/rio/trunk

Subversion Repositories rio

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  • This comparison shows the changes necessary to convert path 
    /rio/branches/parallelSymbols/rtl
    from Rev 10 to Rev 11
    ↔ Reverse comparison
  •

Rev 10 → Rev 11

/vhdl/RioSerial.vhd
46,9 → 46,22
-------------------------------------------------------------------------------
-- RioSerial
--
-- Generics
-- --------
-- TIMEOUT_WIDTH - The number of bits to be used in the portLinkTimeout signal.
-- NUMBER_WORDS - The number of parallell words that the data symbols can
-- contain. This sizes the data buses. It can be used to increase the bandwidth
-- of the core. Note that it cannot be larger than 4. This is since two
-- packets may be completed at the same tick and the interface to the
-- packetBuffer cannot handle more than one packets in one tick.
--
-- Signals
-- -------
-- System signals.
-- clk - System clock.
-- areset_n - System reset. Asynchronous, active low.
--
-- Configuration signals. These are used to change the runtime behaviour.
-- portLinkTimeout_i - The number of ticks to wait for a packet-accepted before
-- a timeout occurrs.
-- linkInitialized_o - Indicates if a link partner is answering with valid
144,18 → 157,24
-- outboundSymbolRead_i has been asserted.
-- outboundSymbolRead_i - Indicate that outboundSymbol_o has been read and a
-- new value could be accepted. It should be active for one tick.
-- outboundSymbol_o - The outbound symbol. The two MSB bits are the type of the
-- symbol.
-- bit 34-33
-- 00=IDLE, the rest of the bits are not used.
-- 01=CONTROL, the control symbols payload (24 bits) are placed in the MSB
-- part of the symbol data.
-- 10=ERROR, the rest of the bits are not used.
-- 11=DATA, all the remaining bits contain the data-symbol payload.
-- REMARK: Update this comment...
-- outboundSymbol_o - The outbound symbol. It is divided into two parts,
-- symbolType and symbolContent.
-- symbolType - The two MSB bits are the type of the symbol according to
-- table below:
-- 00=IDLE, the rest of the bits are not used.
-- 01=CONTROL, the control symbols payload (24 bits) are placed in the MSB
-- part of the symbolContent.
-- 10=ERROR, the rest of the bits are not used.
-- 11=DATA, all the remaining bits contain the number of valid words and
-- the payload of the symbol.
-- symbolContent - The rest of the bits are symbol content. If there are
-- multiple words in the symbols they must be set to zero. The first
-- received word is placed in the MSB part of this field.
-- inboundSymbolFull_o - An asserted signal indicates that no more inbound
-- symbols can be accepted.
-- inboundSymbolWrite_i - Indicate that inboundSymbol_i contains valid
-- information that should be forwarded. Should be active for one tick.
-- information that should be forwarded. Should be active for one tick.
-- inboundSymbol_i - The inbound symbol. See outboundSymbol_o for formating.
-------------------------------------------------------------------------------
library ieee;
169,7 → 188,8
-------------------------------------------------------------------------------
entity RioSerial is
generic(
TIMEOUT_WIDTH : natural);
TIMEOUT_WIDTH : natural;
NUMBER_WORDS : natural range 1 to 4 := 1);
port(
-- System signals.
clk : in std_logic;
202,7 → 222,7
readContentEmpty_i : in std_logic;
readContent_o : out std_logic;
readContentEnd_i : in std_logic;
readContentData_i : in std_logic_vector(31 downto 0);
readContentData_i : in std_logic_vector(2+(32*NUMBER_WORDS-1) downto 0);
 
-- Inbound frame interface.
writeFrameFull_i : in std_logic;
209,16 → 229,16
writeFrame_o : out std_logic;
writeFrameAbort_o : out std_logic;
writeContent_o : out std_logic;
writeContentData_o : out std_logic_vector(31 downto 0);
writeContentData_o : out std_logic_vector(2+(32*NUMBER_WORDS-1) downto 0);
 
-- PCS layer signals.
portInitialized_i : in std_logic;
outboundSymbolEmpty_o : out std_logic;
outboundSymbolRead_i : in std_logic;
outboundSymbol_o : out std_logic_vector(33 downto 0);
outboundSymbol_o : out std_logic_vector(((2+32)*NUMBER_WORDS-1) downto 0);
inboundSymbolFull_o : out std_logic;
inboundSymbolWrite_i : in std_logic;
inboundSymbol_i : in std_logic_vector(33 downto 0));
inboundSymbol_i : in std_logic_vector(((2+32)*NUMBER_WORDS-1) downto 0));
end entity;
 
 
245,7 → 265,8
component RioTransmitter is
generic(
TIMEOUT_WIDTH : natural);
TIMEOUT_WIDTH : natural;
NUMBER_WORDS : natural range 1 to 4 := 1);
port(
clk : in std_logic;
areset_n : in std_logic;
263,7 → 284,7
portInitialized_i : in std_logic;
txFull_i : in std_logic;
txWrite_o : out std_logic;
txControl_o : out std_logic_vector(1 downto 0);
txType_o : out std_logic_vector(1 downto 0);
txData_o : out std_logic_vector(31 downto 0);
 
txControlEmpty_i : in std_logic;
287,10 → 308,13
readContentEmpty_i : in std_logic;
readContent_o : out std_logic;
readContentEnd_i : in std_logic;
readContentData_i : in std_logic_vector(31 downto 0));
readContentWords_i : in std_logic_vector(1 downto 0);
readContentData_i : in std_logic_vector(32*NUMBER_WORDS-1 downto 0));
end component;
 
component RioReceiver is
generic(
NUMBER_WORDS : natural range 1 to 4 := 1);
port(
clk : in std_logic;
areset_n : in std_logic;
304,13 → 328,13
portInitialized_i : in std_logic;
rxEmpty_i : in std_logic;
rxRead_o : out std_logic;
rxControl_i : in std_logic_vector(1 downto 0);
rxData_i : in std_logic_vector(31 downto 0);
rxType_i : in std_logic_vector(2*NUMBER_WORDS-1 downto 0);
rxData_i : in std_logic_vector(32*NUMBER_WORDS-1 downto 0);
 
txControlWrite_o : out std_logic;
txControlSymbol_o : out std_logic_vector(12 downto 0);
rxControlWrite_o : out std_logic;
rxControlSymbol_o : out std_logic_vector(12 downto 0);
txControlWrite_o : out std_logic_vector(NUMBER_WORDS-1 downto 0);
txControlSymbol_o : out std_logic_vector(12*NUMBER_WORDS downto 0);
rxControlWrite_o : out std_logic_vector(NUMBER_WORDS-1 downto 0);
rxControlSymbol_o : out std_logic_vector(12*NUMBER_WORDS downto 0);
 
ackIdStatus_o : out std_logic_vector(4 downto 0);
linkInitialized_o : out std_logic;
319,7 → 343,8
writeFrame_o : out std_logic;
writeFrameAbort_o : out std_logic;
writeContent_o : out std_logic;
writeContentData_o : out std_logic_vector(31 downto 0));
writeContentWords_o : out std_logic_vector(1 downto 0);
writeContentData_o : out std_logic_vector(32*NUMBER_WORDS-1 downto 0));
end component;
 
signal linkInitializedRx : std_logic;
326,29 → 351,29
signal linkInitializedTx : std_logic;
signal ackIdStatus : std_logic_vector(4 downto 0);
signal txControlWrite : std_logic;
signal txControlWriteSymbol : std_logic_vector(12 downto 0);
signal txControlReadEmpty : std_logic;
signal txControlRead : std_logic;
signal txControlReadSymbol : std_logic_vector(12 downto 0);
signal txControlWrite : std_logic_vector(NUMBER_WORDS-1 downto 0);
signal txControlWriteSymbol : std_logic_vector(12*NUMBER_WORDS downto 0);
signal txControlReadEmpty : std_logic_vector(NUMBER_WORDS-1 downto 0);
signal txControlRead : std_logic_vector(NUMBER_WORDS-1 downto 0);
signal txControlReadSymbol : std_logic_vector(12*NUMBER_WORDS downto 0);
 
signal rxControlWrite : std_logic;
signal rxControlWriteSymbol : std_logic_vector(12 downto 0);
signal rxControlReadEmpty : std_logic;
signal rxControlRead : std_logic;
signal rxControlReadSymbol : std_logic_vector(12 downto 0);
signal rxControlWrite : std_logic_vector(NUMBER_WORDS-1 downto 0);
signal rxControlWriteSymbol : std_logic_vector(12*NUMBER_WORDS downto 0);
signal rxControlReadEmpty : std_logic_vector(NUMBER_WORDS-1 downto 0);
signal rxControlRead : std_logic_vector(NUMBER_WORDS-1 downto 0);
signal rxControlReadSymbol : std_logic_vector(12*NUMBER_WORDS downto 0);
 
signal outboundFull : std_logic;
signal outboundWrite : std_logic;
signal outboundControl : std_logic_vector(1 downto 0);
signal outboundData : std_logic_vector(31 downto 0);
signal outboundSymbol : std_logic_vector(33 downto 0);
signal outboundType : std_logic_vector(1 downto 0);
signal outboundData : std_logic_vector(32*NUMBER_WORDS-1 downto 0);
signal outboundSymbol : std_logic_vector(2+(32*NUMBER_WORDS-1) downto 0);
 
signal inboundEmpty : std_logic;
signal inboundRead : std_logic;
signal inboundControl : std_logic_vector(1 downto 0);
signal inboundData : std_logic_vector(31 downto 0);
signal inboundSymbol : std_logic_vector(33 downto 0);
signal inboundType : std_logic_vector(1 downto 0);
signal inboundData : std_logic_vector(32*NUMBER_WORDS-1 downto 0);
signal inboundSymbol : std_logic_vector(((2+32)*NUMBER_WORDS-1) downto 0);
 
begin
 
361,7 → 386,8
Transmitter: RioTransmitter
generic map(
TIMEOUT_WIDTH=>TIMEOUT_WIDTH)
TIMEOUT_WIDTH=>TIMEOUT_WIDTH,
NUMBER_WORDS=>NUMBER_WORDS)
port map(
clk=>clk, areset_n=>areset_n,
portLinkTimeout_i=>portLinkTimeout_i,
374,11 → 400,11
outboundAckId_o=>outboundAckId_o,
portInitialized_i=>portInitialized_i,
txFull_i=>outboundFull, txWrite_o=>outboundWrite,
txControl_o=>outboundControl, txData_o=>outboundData,
txControlEmpty_i=>txControlReadEmpty, txControlSymbol_i=>txControlReadSymbol,
txControlUpdate_o=>txControlRead,
rxControlEmpty_i=>rxControlReadEmpty, rxControlSymbol_i=>rxControlReadSymbol,
rxControlUpdate_o=>rxControlRead,
txType_o=>outboundType, txData_o=>outboundData,
txControlEmpty_i=>txControlReadEmpty(0), txControlSymbol_i=>txControlReadSymbol,
txControlUpdate_o=>txControlRead(0),
rxControlEmpty_i=>rxControlReadEmpty(0), rxControlSymbol_i=>rxControlReadSymbol,
rxControlUpdate_o=>rxControlRead(0),
linkInitialized_o=>linkInitializedTx,
linkInitialized_i=>linkInitializedRx, ackIdStatus_i=>ackIdStatus,
readFrameEmpty_i=>readFrameEmpty_i, readFrame_o=>readFrame_o,
386,23 → 412,36
readWindowEmpty_i=>readWindowEmpty_i,
readWindowReset_o=>readWindowReset_o, readWindowNext_o=>readWindowNext_o,
readContentEmpty_i=>readContentEmpty_i, readContent_o=>readContent_o,
readContentEnd_i=>readContentEnd_i, readContentData_i=>readContentData_i);
readContentEnd_i=>readContentEnd_i,
readContentWords_i=>readContentData_i(2+(32*NUMBER_WORDS-1) downto 1+(32*NUMBER_WORDS-1)),
readContentData_i=>readContentData_i(32*NUMBER_WORDS-1 downto 0));
 
TxSymbolFifo: RioFifo1
generic map(WIDTH=>13)
port map(
clk=>clk, areset_n=>areset_n,
empty_o=>txControlReadEmpty, read_i=>txControlRead, data_o=>txControlReadSymbol,
full_o=>open, write_i=>txControlWrite, data_i=>txControlWriteSymbol);
SymbolFifo: for i in 0 to NUMBER_WORDS-1 generate
TxSymbolFifo: RioFifo1
generic map(WIDTH=>13)
port map(
clk=>clk, areset_n=>areset_n,
empty_o=>txControlReadEmpty(i),
read_i=>txControlRead(i),
data_o=>txControlReadSymbol(12*(i+1) downto 12*i),
full_o=>open,
write_i=>txControlWrite(i),
data_i=>txControlWriteSymbol(12*(i+1) downto 12*i));
 
RxSymbolFifo: RioFifo1
generic map(WIDTH=>13)
port map(
clk=>clk, areset_n=>areset_n,
empty_o=>rxControlReadEmpty, read_i=>rxControlRead, data_o=>rxControlReadSymbol,
full_o=>open, write_i=>rxControlWrite, data_i=>rxControlWriteSymbol);
 
RxSymbolFifo: RioFifo1
generic map(WIDTH=>13)
port map(
clk=>clk, areset_n=>areset_n,
empty_o=>rxControlReadEmpty(i),
read_i=>rxControlRead(i),
data_o=>rxControlReadSymbol(12*(i+1) downto 12*i),
full_o=>open,
write_i=>rxControlWrite(i),
data_i=>rxControlWriteSymbol(12*(i+1) downto 12*i));
end generate;
Receiver: RioReceiver
generic map(NUMBER_WORDS=>NUMBER_WORDS)
port map(
clk=>clk, areset_n=>areset_n,
portEnable_i=>inputPortEnable_i,
411,7 → 450,7
inboundAckId_o=>inboundAckId_o,
portInitialized_i=>portInitialized_i,
rxEmpty_i=>inboundEmpty, rxRead_o=>inboundRead,
rxControl_i=>inboundControl, rxData_i=>inboundData,
rxType_i=>inboundType, rxData_i=>inboundData,
txControlWrite_o=>txControlWrite, txControlSymbol_o=>txControlWriteSymbol,
rxControlWrite_o=>rxControlWrite, rxControlSymbol_o=>rxControlWriteSymbol,
ackIdStatus_o=>ackIdStatus,
418,24 → 457,26
linkInitialized_o=>linkInitializedRx,
writeFrameFull_i=>writeFrameFull_i,
writeFrame_o=>writeFrame_o, writeFrameAbort_o=>writeFrameAbort_o,
writeContent_o=>writeContent_o, writeContentData_o=>writeContentData_o);
writeContent_o=>writeContent_o,
writeContentWords_o=>writeContentData_o(2+(32*NUMBER_WORDS-1) downto 1+(32*NUMBER_WORDS-1)),
writeContentData_o=>writeContentData_o(32*NUMBER_WORDS-1 downto 0));
 
-----------------------------------------------------------------------------
-- PCS layer FIFO interface.
-----------------------------------------------------------------------------
outboundSymbol <= outboundControl & outboundData;
outboundSymbol <= outboundType & outboundData;
OutboundSymbolFifo: RioFifo1
generic map(WIDTH=>34)
generic map(WIDTH=>2+32*NUMBER_WORDS)
port map(
clk=>clk, areset_n=>areset_n,
empty_o=>outboundSymbolEmpty_o, read_i=>outboundSymbolRead_i, data_o=>outboundSymbol_o,
full_o=>outboundFull, write_i=>outboundWrite, data_i=>outboundSymbol);
inboundControl <= inboundSymbol(33 downto 32);
inboundData <= inboundSymbol(31 downto 0);
inboundType <= inboundSymbol(2+(32*NUMBER_WORDS-1) downto 1+(32*NUMBER_WORDS-1));
inboundData <= inboundSymbol(32*NUMBER_WORDS-1 downto 0);
InboundSymbolFifo: RioFifo1
generic map(WIDTH=>34)
generic map(WIDTH=>2+32*NUMBER_WORDS)
port map(
clk=>clk, areset_n=>areset_n,
empty_o=>inboundEmpty, read_i=>inboundRead, data_o=>inboundSymbol,
459,7 → 500,8
-------------------------------------------------------------------------------
entity RioTransmitter is
generic(
TIMEOUT_WIDTH : natural);
TIMEOUT_WIDTH : natural;
NUMBER_WORDS : natural range 1 to 4 := 1);
port(
-- System signals.
clk : in std_logic;
481,8 → 523,8
portInitialized_i : in std_logic;
txFull_i : in std_logic;
txWrite_o : out std_logic;
txControl_o : out std_logic_vector(1 downto 0);
txData_o : out std_logic_vector(31 downto 0);
txType_o : out std_logic_vector(2*NUMBER_WORDS-1 downto 0);
txData_o : out std_logic_vector(32*NUMBER_WORDS-1 downto 0);
 
-- Control symbols aimed to the transmitter.
txControlEmpty_i : in std_logic;
510,7 → 552,8
readContentEmpty_i : in std_logic;
readContent_o : out std_logic;
readContentEnd_i : in std_logic;
readContentData_i : in std_logic_vector(31 downto 0));
readContentWords_i : in std_logic_vector(1 downto 0);
readContentData_i : in std_logic_vector(32*NUMBER_WORDS-1 downto 0));
end entity;
 
 
521,6 → 564,94
 
constant NUMBER_STATUS_TRANSMIT : natural := 15;
constant NUMBER_LINK_RESPONSE_RETRIES : natural := 2;
 
component RioTransmitterCore is
generic(
TIMEOUT_WIDTH : natural;
NUMBER_WORDS : natural range 1 to 4 := 1);
port(
-- System signals.
clk : in std_logic;
areset_n : in std_logic;
 
-- Status signals used for maintenance.
portLinkTimeout_i : in std_logic_vector(TIMEOUT_WIDTH-1 downto 0);
portEnable_i : in std_logic;
 
-- Port output interface.
portInitialized_i : in std_logic;
txFull_i : in std_logic;
txWrite_o : out std_logic;
txType_o : out std_logic_vector(2*NUMBER_WORDS-1 downto 0);
txData_o : out std_logic_vector(32*NUMBER_WORDS-1 downto 0);
 
-- Control symbols aimed to the transmitter.
txControlEmpty_i : in std_logic;
txControlSymbol_i : in std_logic_vector(13*NUMBER_WORDS-1 downto 0);
txControlUpdate_o : out std_logic;
 
-- Control symbols from the receiver to send.
rxControlEmpty_i : in std_logic;
rxControlSymbol_i : in std_logic_vector(13*NUMBER_WORDS-1 downto 0);
rxControlUpdate_o : out std_logic;
 
-- Internal signalling from the receiver part.
linkInitialized_o : out std_logic;
linkInitialized_i : in std_logic;
ackIdStatus_i : in std_logic_vector(4 downto 0);
 
-- The current time used for timeout calculations.
timeCurrent_i : in std_logic_vector(TIMEOUT_WIDTH downto 0);
-- Internal core variables for cascading.
timeSentWrite_o : out std_logic;
timeSentWriteAddress_o : out std_logic_vector(4 downto 0);
timeSentWriteData_o : out std_logic_vector(TIMEOUT_WIDTH downto 0);
timeSentReadAddress_o : out std_logic_vector(4 downto 0);
timeSentReadData_i : in std_logic_vector(TIMEOUT_WIDTH downto 0);
operational_i : in std_logic;
operational_o : out std_logic;
ackId_i : in std_logic_vector(4 downto 0);
ackId_o : out std_logic_vector(4 downto 0);
bufferStatus_i : in std_logic_vector(4 downto 0);
bufferStatus_o : out std_logic_vector(4 downto 0);
statusReceived_i : in std_logic;
statusReceived_o : out std_logic;
numberSentLinkRequests_i : in std_logic_vector(1 downto 0);
numberSentLinkRequests_o : out std_logic_vector(1 downto 0);
outputErrorStopped_i : in std_logic;
outputErrorStopped_o : out std_logic;
recoverActive_i : in std_logic;
recoverActive_o : out std_logic;
recoverCounter_i : in std_logic_vector(4 downto 0);
recoverCounter_o : out std_logic_vector(4 downto 0);
ackIdWindow_i : in std_logic_vector(4 downto 0);
ackIdWindow_o : out std_logic_vector(4 downto 0);
frameState_i : in std_logic_vector(4 downto 0);
frameState_o : out std_logic_vector(4 downto 0);
frameWordCounter_i : in std_logic_vector(1 downto 0);
frameWordCounter_o : out std_logic_vector(1 downto 0);
frameContent_i : in std_logic_vector(32*NUMBER_WORDS-1 downto 0);
frameContent_o : out std_logic_vector(32*NUMBER_WORDS-1 downto 0);
counter_i : in std_logic_vector(3 downto 0);
counter_o : out std_logic_vector(3 downto 0);
symbolsTransmitted_i : in std_logic_vector(7 downto 0);
symbolsTransmitted_o : out std_logic_vector(7 downto 0);
-- Frame buffer interface.
readFrameEmpty_i : in std_logic;
readFrame_o : out std_logic;
readFrameRestart_o : out std_logic;
readFrameAborted_i : in std_logic;
readWindowEmpty_i : in std_logic;
readWindowReset_o : out std_logic;
readWindowNext_o : out std_logic;
readContentEmpty_i : in std_logic;
readContent_o : out std_logic;
readContentEnd_i : in std_logic;
readContentWords_i : in std_logic_vector(1 downto 0);
readContentData_i : in std_logic_vector(32*NUMBER_WORDS-1 downto 0));
end component;
component MemorySimpleDualPortAsync is
generic(
536,412 → 667,390
addressB_i : in std_logic_vector(ADDRESS_WIDTH-1 downto 0);
dataB_o : out std_logic_vector(DATA_WIDTH-1 downto 0));
end component;
component Crc5ITU is
port(
d_i : in std_logic_vector(18 downto 0);
crc_o : out std_logic_vector(4 downto 0));
end component;
 
type StateType is (STATE_UNINITIALIZED, STATE_PORT_INITIALIZED,
STATE_NORMAL,
STATE_OUTPUT_RETRY_STOPPED,
STATE_SEND_LINK_REQUEST, STATE_OUTPUT_ERROR_STOPPED,
STATE_RECOVER, STATE_FATAL_ERROR);
signal stateCurrent, stateNext : StateType;
 
signal statusReceivedCurrent, statusReceivedNext : std_logic;
signal counterCurrent, counterNext : natural range 0 to 15;
signal symbolsTransmittedCurrent, symbolsTransmittedNext : natural range 0 to 255;
signal timeCurrent : std_logic_vector(TIMEOUT_WIDTH downto 0);
signal timeSentWrite : std_logic;
signal timeSentWriteAddress : std_logic_vector(4 downto 0);
signal timeSentWriteData : std_logic_vector(TIMEOUT_WIDTH downto 0);
signal timeSentReadAddress : std_logic_vector(4 downto 0);
signal timeSentReadData : std_logic_vector(TIMEOUT_WIDTH downto 0);
type FrameStateType is (FRAME_START, FRAME_CHECK, FRAME_ACKID, FRAME_BODY, FRAME_END);
signal frameStateCurrent, frameStateNext : FrameStateType;
signal ackIdCurrent, ackIdNext : unsigned(4 downto 0) := (others=>'0');
signal ackIdWindowCurrent, ackIdWindowNext : unsigned(4 downto 0) := (others=>'0');
signal operationalCurrent, operationalNext : std_logic;
signal ackIdCurrent, ackIdNext : std_logic_vector(4 downto 0);
signal bufferStatusCurrent, bufferStatusNext : std_logic_vector(4 downto 0);
signal stype0 : std_logic_vector(2 downto 0);
signal parameter0 : std_logic_vector(4 downto 0);
signal parameter1 : std_logic_vector(4 downto 0);
signal stype1 : std_logic_vector(2 downto 0);
signal cmd : std_logic_vector(2 downto 0);
signal txControlStype0 : std_logic_vector(2 downto 0);
signal txControlParameter0 : std_logic_vector(4 downto 0);
signal txControlParameter1 : std_logic_vector(4 downto 0);
signal statusReceivedCurrent, statusReceivedNext : std_logic;
signal numberSentLinkRequestsCurrent, numberSentLinkRequestsNext : std_logic_vector(1 downto 0);
signal outputErrorStoppedCurrent, outputErrorStoppedNext : std_logic;
signal recoverActiveCurrent, recoverActiveNext : std_logic;
signal recoverCounterCurrent, recoverCounterNext : std_logic_vector(4 downto 0);
signal ackIdWindowCurrent, ackIdWindowNext : std_logic_vector(4 downto 0);
signal frameStateCurrent, frameStateNext : std_logic_vector(4 downto 0);
signal frameWordCounterCurrent, frameWordCounterNext : std_logic_vector(1 downto 0);
signal frameContentCurrent, frameContentNext : std_logic_vector(32*NUMBER_WORDS-1 downto 0);
signal counterCurrent, counterNext : std_logic_vector(3 downto 0);
signal symbolsTransmittedCurrent, symbolsTransmittedNext : std_logic_vector(7 downto 0);
 
signal rxControlStype0 : std_logic_vector(2 downto 0);
signal rxControlParameter0 : std_logic_vector(4 downto 0);
signal rxControlParameter1 : std_logic_vector(4 downto 0);
 
signal symbolWrite : std_logic;
signal symbolType : std_logic_vector(1 downto 0);
signal symbolControl : std_logic_vector(31 downto 0);
signal symbolData : std_logic_vector(31 downto 0);
signal crcCalculated : std_logic_vector(4 downto 0);
 
signal timeoutWrite : std_logic;
signal timeoutCounter : unsigned(TIMEOUT_WIDTH downto 0);
signal timeoutFrame : unsigned(TIMEOUT_WIDTH downto 0);
signal timeoutElapsed : unsigned(TIMEOUT_WIDTH downto 0);
signal timeoutDelta : unsigned(TIMEOUT_WIDTH downto 0);
signal timeoutExpired : std_logic;
 
signal timeoutAddress : std_logic_vector(4 downto 0);
signal timeoutMemoryOut : std_logic_vector(TIMEOUT_WIDTH downto 0);
begin
 
linkInitialized_o <= '0' when ((stateCurrent = STATE_UNINITIALIZED) or
(stateCurrent = STATE_PORT_INITIALIZED)) else '1';
-----------------------------------------------------------------------------
-- Assign control symbol from fifo signals.
-----------------------------------------------------------------------------
txControlStype0 <= txControlSymbol_i(12 downto 10);
txControlParameter0 <= txControlSymbol_i(9 downto 5);
txControlParameter1 <= txControlSymbol_i(4 downto 0);
 
rxControlStype0 <= rxControlSymbol_i(12 downto 10);
rxControlParameter0 <= rxControlSymbol_i(9 downto 5);
rxControlParameter1 <= rxControlSymbol_i(4 downto 0);
 
-----------------------------------------------------------------------------
-- Outbound symbol creation logic.
-----------------------------------------------------------------------------
 
symbolControl(31 downto 29) <= stype0;
symbolControl(28 downto 24) <= parameter0;
symbolControl(23 downto 19) <= parameter1;
symbolControl(18 downto 16) <= stype1;
symbolControl(15 downto 13) <= cmd;
symbolControl(12 downto 8) <= crcCalculated;
symbolControl(7 downto 0) <= x"00";
 
Crc5Calculator: Crc5ITU
port map(
d_i=>symbolControl(31 downto 13), crc_o=>crcCalculated);
 
txWrite_o <= symbolWrite;
txControl_o <= symbolType;
txData_o <= symbolControl when (symbolType = SYMBOL_CONTROL) else symbolData;
-----------------------------------------------------------------------------
-- Packet timeout logic.
-----------------------------------------------------------------------------
 
-- Note that the timer is one bit larger to be able to detect a timeout on a
-- free-running counter.
process(areset_n, clk)
begin
if (areset_n = '0') then
timeoutCounter <= (others=>'0');
timeCurrent <= (others=>'0');
elsif (clk'event and clk = '1') then
timeoutCounter <= timeoutCounter + 1;
timeCurrent <= std_logic_vector(unsigned(timeCurrent) + 1);
end if;
end process;
 
timeoutElapsed <= timeoutCounter - timeoutFrame;
timeoutDelta <= unsigned('0' & portLinkTimeout_i) - timeoutElapsed;
timeoutExpired <= timeoutDelta(TIMEOUT_WIDTH);
timeoutFrame <= unsigned(timeoutMemoryOut);
TimeoutMemory: MemorySimpleDualPortAsync
generic map(ADDRESS_WIDTH=>5, DATA_WIDTH=>TIMEOUT_WIDTH+1, INIT_VALUE=>'0')
port map(
clkA_i=>clk, enableA_i=>timeoutWrite,
addressA_i=>timeoutAddress, dataA_i=>std_logic_vector(timeoutCounter),
addressB_i=>std_logic_vector(ackIdCurrent), dataB_o=>timeoutMemoryOut);
clkA_i=>clk, enableA_i=>timeSentWrite,
addressA_i=>timeSentWriteAddress, dataA_i=>timeSentWriteData,
addressB_i=>timeSentReadAddress, dataB_o=>timeSentReadData);
-----------------------------------------------------------------------------
-- Main outbound symbol handler, synchronous part.
-----------------------------------------------------------------------------
process(areset_n, clk)
begin
if (areset_n = '0') then
stateCurrent <= STATE_UNINITIALIZED;
 
operationalCurrent <= '0';
ackIdCurrent <= (others=>'0');
bufferStatusCurrent <= (others=>'0');
statusReceivedCurrent <= '0';
counterCurrent <= 0;
symbolsTransmittedCurrent <= 0;
frameStateCurrent <= FRAME_START;
ackIdCurrent <= (others => '0');
ackIdWindowCurrent <= (others => '0');
bufferStatusCurrent <= (others => '0');
numberSentLinkRequestsCurrent <= (others=>'0');
outputErrorStoppedCurrent <= '0';
recoverActiveCurrent <= '0';
recoverCounterCurrent <= (others=>'0');
ackIdWindowCurrent <= (others=>'0');
frameStateCurrent <= (others=>'0');
frameWordCounterCurrent <= (others=>'0');
frameContentCurrent <= (others=>'0');
counterCurrent <= (others=>'0');
symbolsTransmittedCurrent <= (others=>'0');
elsif (clk'event and clk = '1') then
stateCurrent <= stateNext;
 
operationalCurrent <= operationalNext;
ackIdCurrent <= ackIdNext;
bufferStatusCurrent <= bufferStatusNext;
statusReceivedCurrent <= statusReceivedNext;
numberSentLinkRequestsCurrent <= numberSentLinkRequestsNext;
outputErrorStoppedCurrent <= outputErrorStoppedNext;
recoverActiveCurrent <= recoverActiveNext;
recoverCounterCurrent <= recoverCounterNext;
ackIdWindowCurrent <= ackIdWindowNext;
frameStateCurrent <= frameStateNext;
frameWordCounterCurrent <= frameWordCounterNext;
frameContentCurrent <= frameContentNext;
counterCurrent <= counterNext;
symbolsTransmittedCurrent <= symbolsTransmittedNext;
frameStateCurrent <= frameStateNext;
ackIdCurrent <= ackIdNext;
ackIdWindowCurrent <= ackIdWindowNext;
bufferStatusCurrent <= bufferStatusNext;
end if;
end process;
-----------------------------------------------------------------------------
-- Main outbound symbol handler, combinatorial part.
-----------------------------------------------------------------------------
process(stateCurrent,
statusReceivedCurrent, counterCurrent,
symbolsTransmittedCurrent,
frameStateCurrent, ackIdCurrent, ackIdWindowCurrent, bufferStatusCurrent,
txControlStype0, txControlParameter0, txControlParameter1,
rxControlStype0, rxControlParameter0, rxControlParameter1,
portEnable_i,
localAckIdWrite_i, clrOutstandingAckId_i,
outstandingAckId_i, outboundAckId_i,
txFull_i,
txControlEmpty_i, txControlSymbol_i,
rxControlEmpty_i, rxControlSymbol_i,
portInitialized_i, linkInitialized_i, ackIdStatus_i,
readFrameEmpty_i, readFrameAborted_i,
readWindowEmpty_i,
readContentEmpty_i, readContentEnd_i, readContentData_i,
timeoutExpired)
begin
stateNext <= stateCurrent;
statusReceivedNext <= statusReceivedCurrent;
counterNext <= counterCurrent;
symbolsTransmittedNext <= symbolsTransmittedCurrent;
frameStateNext <= frameStateCurrent;
ackIdNext <= ackIdCurrent;
ackIdWindowNext <= ackIdWindowCurrent;
bufferStatusNext <= bufferStatusCurrent;
txControlUpdate_o <= '0';
rxControlUpdate_o <= '0';
TxCore: RioTransmitterCore
generic map(TIMEOUT_WIDTH=>TIMEOUT_WIDTH,
NUMBER_WORDS=>NUMBER_WORDS)
port map(
clk=>clk, areset_n=>areset_n,
portLinkTimeout_i=>portLinkTimeout_i, portEnable_i=>portEnable_i,
portInitialized_i=>portInitialized_i,
txFull_i=>txFull_i, txWrite_o=>txWrite_o, txType_o=>txType_o, txData_o=>txData_o,
txControlEmpty_i=>txControlEmpty_i,
txControlSymbol_i=>txControlSymbol_i,
txControlUpdate_o=>txControlUpdate_o,
rxControlEmpty_i=>rxControlEmpty_i,
rxControlSymbol_i=>rxControlSymbol_i,
rxControlUpdate_o=>rxControlUpdate_o,
linkInitialized_o=>linkInitialized_o,
linkInitialized_i=>linkInitialized_i,
ackIdStatus_i=>ackIdStatus_i,
 
readFrame_o <= '0';
readFrameRestart_o <= '0';
readWindowReset_o <= '0';
readWindowNext_o <= '0';
readContent_o <= '0';
timeCurrent_i=>timeCurrent,
timeSentWrite_o=>timeSentWrite,
timeSentWriteAddress_o=>timeSentWriteAddress,
timeSentWriteData_o=>timeSentWriteData,
timeSentReadAddress_o=>timeSentReadAddress,
timeSentReadData_i=>timeSentReadData,
operational_i=>operationalCurrent, operational_o=>operationalNext,
ackId_i=>ackIdCurrent, ackId_o=>ackIdNext,
bufferStatus_i=>bufferStatusCurrent, bufferStatus_o=>bufferStatusNext,
statusReceived_i=>statusReceivedCurrent, statusReceived_o=>statusReceivedNext,
numberSentLinkRequests_i=>numberSentLinkRequestsCurrent, numberSentLinkRequests_o=>numberSentLinkRequestsNext,
outputErrorStopped_i=>outputErrorStoppedCurrent, outputErrorStopped_o=>outputErrorStoppedNext,
recoverActive_i=>recoverActiveCurrent, recoverActive_o=>recoverActiveNext,
recoverCounter_i=>recoverCounterCurrent, recoverCounter_o=>recoverCounterNext,
ackIdWindow_i=>ackIdWindowCurrent, ackIdWindow_o=>ackIdWindowNext,
frameState_i=>frameStateCurrent, frameState_o=>frameStateNext,
frameWordCounter_i=>frameWordCounterCurrent, frameWordCounter_o=>frameWordCounterNext,
frameContent_i=>frameContentCurrent, frameContent_o=>frameContentNext,
counter_i=>counterCurrent, counter_o=>counterNext,
symbolsTransmitted_i=>symbolsTransmittedCurrent, symbolsTransmitted_o=>symbolsTransmittedNext,
 
symbolWrite <= '0';
symbolType <= (others=>'U');
stype0 <= (others=>'U');
parameter0 <= (others=>'U');
parameter1 <= (others=>'U');
stype1 <= (others=>'U');
cmd <= (others=>'U');
symbolData <= (others=>'U');
timeoutWrite <= '0';
timeoutAddress <= (others=>'U');
readFrameEmpty_i=>readFrameEmpty_i,
readFrame_o=>readFrame_o,
readFrameRestart_o=>readFrameRestart_o,
readFrameAborted_i=>readFrameAborted_i,
readWindowEmpty_i=>readWindowEmpty_i,
readWindowReset_o=>readWindowReset_o,
readWindowNext_o=>readWindowNext_o,
readContentEmpty_i=>readContentEmpty_i,
readContent_o=>readContent_o,
readContentEnd_i=>readContentEnd_i,
readContentWords_i=>readContentWords_i,
readContentData_i=>readContentData_i);
 
outstandingAckId_o <= std_logic_vector(ackIdCurrent);
outboundAckId_o <= std_logic_vector(ackIdWindowCurrent);
end architecture;
 
 
 
-------------------------------------------------------------------------------
-- RioTransmitterCore
-------------------------------------------------------------------------------
library ieee;
use ieee.std_logic_1164.all;
use ieee.numeric_std.all;
use work.rio_common.all;
use work.rio_serial_common.all;
 
-------------------------------------------------------------------------------
-- Entity for RioTransmitterCore.
-------------------------------------------------------------------------------
entity RioTransmitterCore is
generic(
TIMEOUT_WIDTH : natural;
NUMBER_WORDS : natural range 1 to 4 := 1);
port(
-- System signals.
clk : in std_logic;
areset_n : in std_logic;
 
-- Status signals used for maintenance.
portLinkTimeout_i : in std_logic_vector(TIMEOUT_WIDTH-1 downto 0);
portEnable_i : in std_logic;
 
-- Port output interface.
portInitialized_i : in std_logic;
txFull_i : in std_logic;
txWrite_o : out std_logic;
txType_o : out std_logic_vector(2*NUMBER_WORDS-1 downto 0);
txData_o : out std_logic_vector(32*NUMBER_WORDS-1 downto 0);
 
-- Control symbols aimed to the transmitter.
txControlEmpty_i : in std_logic;
txControlSymbol_i : in std_logic_vector(13*NUMBER_WORDS-1 downto 0);
txControlUpdate_o : out std_logic;
 
-- Control symbols from the receiver to send.
rxControlEmpty_i : in std_logic;
rxControlSymbol_i : in std_logic_vector(13*NUMBER_WORDS-1 downto 0);
rxControlUpdate_o : out std_logic;
 
-- Internal signalling from the receiver part.
linkInitialized_o : out std_logic;
linkInitialized_i : in std_logic;
ackIdStatus_i : in std_logic_vector(4 downto 0);
 
-- The current time used for timeout calculations.
timeCurrent_i : in std_logic_vector(TIMEOUT_WIDTH downto 0);
-- Check if a localAckIdWrite is active.
if (localAckIdWrite_i = '1') then
-- A localAckIdWrite is active.
-- Internal core variables for cascading.
timeSentWrite_o : out std_logic;
timeSentWriteAddress_o : out std_logic_vector(4 downto 0);
timeSentWriteData_o : out std_logic_vector(TIMEOUT_WIDTH downto 0);
timeSentReadAddress_o : out std_logic_vector(4 downto 0);
timeSentReadData_i : in std_logic_vector(TIMEOUT_WIDTH downto 0);
operational_i : in std_logic;
operational_o : out std_logic;
ackId_i : in std_logic_vector(4 downto 0);
ackId_o : out std_logic_vector(4 downto 0);
bufferStatus_i : in std_logic_vector(4 downto 0);
bufferStatus_o : out std_logic_vector(4 downto 0);
statusReceived_i : in std_logic;
statusReceived_o : out std_logic;
numberSentLinkRequests_i : in std_logic_vector(1 downto 0);
numberSentLinkRequests_o : out std_logic_vector(1 downto 0);
outputErrorStopped_i : in std_logic;
outputErrorStopped_o : out std_logic;
recoverActive_i : in std_logic;
recoverActive_o : out std_logic;
recoverCounter_i : in std_logic_vector(4 downto 0);
recoverCounter_o : out std_logic_vector(4 downto 0);
ackIdWindow_i : in std_logic_vector(4 downto 0);
ackIdWindow_o : out std_logic_vector(4 downto 0);
frameState_i : in std_logic_vector(4 downto 0);
frameState_o : out std_logic_vector(4 downto 0);
frameWordCounter_i : in std_logic_vector(1 downto 0);
frameWordCounter_o : out std_logic_vector(1 downto 0);
frameContent_i : in std_logic_vector(32*NUMBER_WORDS-1 downto 0);
frameContent_o : out std_logic_vector(32*NUMBER_WORDS-1 downto 0);
counter_i : in std_logic_vector(3 downto 0);
counter_o : out std_logic_vector(3 downto 0);
symbolsTransmitted_i : in std_logic_vector(7 downto 0);
symbolsTransmitted_o : out std_logic_vector(7 downto 0);
-- Frame buffer interface.
readFrameEmpty_i : in std_logic;
readFrame_o : out std_logic;
readFrameRestart_o : out std_logic;
readFrameAborted_i : in std_logic;
readWindowEmpty_i : in std_logic;
readWindowReset_o : out std_logic;
readWindowNext_o : out std_logic;
readContentEmpty_i : in std_logic;
readContent_o : out std_logic;
readContentEnd_i : in std_logic;
readContentWords_i : in std_logic_vector(1 downto 0);
readContentData_i : in std_logic_vector(32*NUMBER_WORDS-1 downto 0));
end entity;
 
-- Check if all outstanding packets should be discarded.
if (clrOutstandingAckId_i = '1') then
-- Delete all outbound packets.
-- REMARK: Remove all packets in another way... what if uninitialized???
stateNext <= STATE_RECOVER;
end if;
 
-- Set ackIds.
ackIdNext <= unsigned(outstandingAckId_i);
ackIdWindowNext <= unsigned(outboundAckId_i);
else
-- A localAckIdWrite is not active.
-------------------------------------------------------------------------------
-- Architecture for RioTransmitterCore.
-------------------------------------------------------------------------------
architecture RioTransmitterCoreImpl of RioTransmitterCore is
 
-- Act on the current state.
case (stateCurrent) is
constant NUMBER_STATUS_TRANSMIT : std_logic_vector := "1111";
constant NUMBER_LINK_RESPONSE_RETRIES : std_logic_vector := "10";
 
when STATE_UNINITIALIZED =>
-----------------------------------------------------------------------
-- This state is entered at startup. A port that is not initialized
-- should only transmit idle sequences.
-----------------------------------------------------------------------
-- Check if the port is initialized.
if (portInitialized_i = '0') then
-- Port not initialized.
-- REMARK: Binary coding???
constant FRAME_START : std_logic_vector(4 downto 0) := "00001";
constant FRAME_CHECK : std_logic_vector(4 downto 0) := "00010";
constant FRAME_ACKID : std_logic_vector(4 downto 0) := "00100";
constant FRAME_BODY : std_logic_vector(4 downto 0) := "01000";
constant FRAME_END : std_logic_vector(4 downto 0) := "10000";
component Crc5ITU is
port(
d_i : in std_logic_vector(18 downto 0);
crc_o : out std_logic_vector(4 downto 0));
end component;
 
-- Check if any new symbols from the link partner has been received.
if (txControlEmpty_i = '0') then
-- New symbols have been received.
-- Discard all new symbols in this state.
txControlUpdate_o <= '1';
else
-- No new symbols from the link partner.
-- Dont do anything.
end if;
signal timeSentUpdate : std_logic;
signal timeElapsed : unsigned(TIMEOUT_WIDTH downto 0);
signal timeDelta : unsigned(TIMEOUT_WIDTH downto 0);
signal timeExpired : std_logic;
 
-- Check if any new symbols should be transmitted to the link partner.
if (rxControlEmpty_i = '0') then
-- New symbols should be transmitted.
-- Do not forward any symbols in this state.
rxControlUpdate_o <= '1';
else
-- No new symbols to transmit.
-- Dont do anything.
end if;
signal sendRestartFromRetry, sendRestartFromRetryOut : std_logic;
signal sendLinkRequest, sendLinkRequestOut : std_logic;
 
-- Check if a new symbol should be transmitted.
if (txFull_i = '0') then
-- A new symbol should be transmitted.
signal symbolControlRestartOut, symbolControlRestart : std_logic;
signal symbolControlLinkRequestOut, symbolControlLinkRequest : std_logic;
signal symbolControlStartOut, symbolControlStart : std_logic;
signal symbolControlEndOut, symbolControlEnd : std_logic;
signal symbolDataOut, symbolData : std_logic;
signal symbolDataContentOut, symbolDataContent : std_logic_vector(31 downto 0);
 
-- Send idle sequence.
symbolWrite <= '1';
symbolType <= SYMBOL_IDLE;
else
-- The outbound fifo is full.
-- Dont do anything.
end if;
signal symbolControlStype1 : std_logic;
signal controlValidOut, controlValid : std_logic;
signal stype0Out, stype0 : std_logic_vector(2 downto 0);
signal parameter0Out, parameter0 : std_logic_vector(4 downto 0);
signal parameter1Out, parameter1 : std_logic_vector(4 downto 0);
signal stype1 : std_logic_vector(2 downto 0);
signal cmd : std_logic_vector(2 downto 0);
signal dataValid : std_logic;
signal dataContent : std_logic_vector(31 downto 0);
signal controlContent : std_logic_vector(31 downto 0);
signal crc5 : std_logic_vector(4 downto 0);
signal txControlStype0 : std_logic_vector(2 downto 0);
signal txControlParameter0 : std_logic_vector(4 downto 0);
signal txControlParameter1 : std_logic_vector(4 downto 0);
 
-- Check if a new full packet is ready.
if (readFrameEmpty_i = '0') then
-- A new full packet is ready.
-- It is not possible to send the packet now. If the packet is not
-- discarded it might congest the full system if the link does not
-- go initialized. To avoid a congested switch, the packet is
-- discarded and will have to be resent by the source when the link
-- is up and running.
readFrame_o <= '1';
else
-- No new full packets are ready.
-- Dont do anything.
end if;
else
-- Port is initialized.
-- Go to the initialized state and reset the counters.
statusReceivedNext <= '0';
counterNext <= NUMBER_STATUS_TRANSMIT;
symbolsTransmittedNext <= 0;
stateNext <= STATE_PORT_INITIALIZED;
end if;
when STATE_PORT_INITIALIZED =>
-----------------------------------------------------------------------
-- The specification requires a status control symbol being sent at
-- least every 1024 code word until an error-free status has been
-- received. This implies that at most 256 idle sequences should be
-- sent in between status control symbols. Once an error-free status has
-- been received, status symbols may be sent more rapidly. At least 15
-- statuses has to be transmitted once an error-free status has been
-- received.
---------------------------------------------------------------------
signal rxControlStype0 : std_logic_vector(2 downto 0);
signal rxControlParameter0 : std_logic_vector(4 downto 0);
signal rxControlParameter1 : std_logic_vector(4 downto 0);
 
-- Check if the port is initialized.
if (portInitialized_i = '1') then
-- Port is initialized.
begin
 
-- Check if we are ready to change state to linkInitialized.
if ((linkInitialized_i = '1') and (counterCurrent = 0)) then
-- Receiver has received enough error free status symbols and we have
-- transmitted enough.
linkInitialized_o <= operational_i;
-----------------------------------------------------------------------------
-- N-3
-- Receive stuff from link-partner and timeout supervision.
-- Input: ackId, ackIdWindow, timeoutExpired
-- Output: sendLinkRequest, sendRestartFromRetry, ackId,
-----------------------------------------------------------------------------
 
-- Initialize framing before entering the normal state.
ackIdWindowNext <= ackIdCurrent;
frameStateNext <= FRAME_START;
readWindowReset_o <= '1';
-- Considder the link initialized.
stateNext <= STATE_NORMAL;
else
-- Not ready to change state to linkInitialized.
-- Dont do anything.
end if;
-- Check if any new symbols from the link partner has been received.
if (txControlEmpty_i = '0') then
-- New symbols have been received.
timeSentReadAddress_o <= ackId_i;
timeElapsed <= unsigned(timeCurrent_i) - unsigned(timeSentReadData_i);
timeDelta <= unsigned('0' & portLinkTimeout_i) - timeElapsed;
timeExpired <= timeDelta(TIMEOUT_WIDTH);
 
-- Check if the new symbol is a status.
if (txControlStype0 = STYPE0_STATUS) then
-- A new status control symbol has been received.
statusReceivedNext <= '1';
-- Set the ackId and the linkpartner buffer status to what is indicated
-- in the received control symbol.
ackIdNext <= unsigned(txControlParameter0);
bufferStatusNext <= txControlParameter1;
else
-- Did not receive a status control symbol.
-- Discard it.
end if;
process(clk, areset_n)
begin
if (areset_n = '0') then
sendRestartFromRetry <= '0';
sendLinkRequest <= '0';
elsif (clk'event and clk = '1') then
sendRestartFromRetry <= sendRestartFromRetryOut;
sendLinkRequest <= sendLinkRequestOut;
end if;
end process;
-- REMARK: Reset statusReceived at startup...
process(outputErrorStopped_i, recoverActive_i, recoverCounter_i, ackId_i, bufferStatus_i,
statusReceived_i, numberSentLinkRequests_i)
begin
txControlUpdate_o <= '0';
outputErrorStopped_o <= outputErrorStopped_i;
recoverActive_o <= recoverActive_i;
recoverCounter_o <= recoverCounter_i;
ackId_o <= ackId_i;
bufferStatus_o <= bufferStatus_i;
statusReceived_o <= statusReceived_i;
numberSentLinkRequests_o <= numberSentLinkRequests_i;
 
-- Update to the next control symbol received by the receiver.
txControlUpdate_o <= '1';
else
-- No new symbols from the link partner.
-- Dont do anything.
end if;
sendRestartFromRetryOut <= '0';
sendLinkRequestOut <= '0';
 
-- Check if any new symbols should be transmitted to the link partner.
if (rxControlEmpty_i = '0') then
-- New symbols should be transmitted.
-- Do not forward any symbols in this state.
rxControlUpdate_o <= '1';
if (recoverActive_i = '1') then
if (ackId_i /= recoverCounter_i) then
ackId_o <= std_logic_vector(unsigned(ackId_i) + 1);
else
recoverActive_o <= '0';
outputErrorStopped_o <= '0';
end if;
else
if (txFull_i = '0') then
if (operational_i = '0') then
if (txControlEmpty_i = '0') then
if (txControlStype0 = STYPE0_STATUS) then
-- A status-control symbol has been received.
ackId_o <= txControlParameter0;
bufferStatus_o <= txControlParameter1;
statusReceived_o <= '1';
else
-- No new symbols to transmit.
-- Dont do anything.
-- Discard all other received symbols in this state.
end if;
txControlUpdate_o <= '1';
end if;
else
-- Check if the oldest frame timeout has expired.
if ((ackId_i /= ackIdWindow_i) and
(timeExpired = '1')) then
-- There has been a timeout on a transmitted frame.
 
-- Check if a new symbol may be transmitted.
if (txFull_i = '0') then
-- A new symbol can be transmitted.
 
-- Check if idle sequence or a status symbol should be transmitted.
if (((statusReceivedCurrent = '0') and (symbolsTransmittedCurrent = 255)) or
((statusReceivedCurrent = '1') and (symbolsTransmittedCurrent > 15))) then
-- A status symbol should be transmitted.
if (outputErrorStopped_i = '1') then
-- Count the number of retransmissions and abort if
-- no reply has been received for too many times.
if (unsigned(numberSentLinkRequests_i) /= 0) then
-- Not sent link-request too many times.
-- Send a status control symbol to the link partner.
symbolWrite <= '1';
symbolType <= SYMBOL_CONTROL;
stype0 <= STYPE0_STATUS;
parameter0 <= ackIdStatus_i;
parameter1 <= "11111";
stype1 <= STYPE1_NOP;
cmd <= "000";
 
-- Reset idle sequence transmission counter.
symbolsTransmittedNext <= 0;
 
-- Check if the number of transmitted statuses should be updated.
if (statusReceivedCurrent = '1') and (counterCurrent /= 0) then
counterNext <= counterCurrent - 1;
end if;
-- Send another link-request.
sendLinkRequestOut <= '1';
numberSentLinkRequests_o <= std_logic_vector(unsigned(numberSentLinkRequests_i) - 1);
else
-- A idle sequence should be transmitted.
symbolWrite <= '1';
symbolType <= SYMBOL_IDLE;
 
-- Increment the idle sequence transmission counter.
symbolsTransmittedNext <= symbolsTransmittedCurrent + 1;
-- No response for too many times.
-- REMARK: What to do here???
--readWindowReset_o <= '1';
--stateNext <= STATE_UNINITIALIZED;
end if;
else
-- Cannot send a new symbol.
-- Dont do anything.
sendLinkRequestOut <= '1';
numberSentLinkRequests_o <= NUMBER_LINK_RESPONSE_RETRIES;
outputErrorStopped_o <= '1';
end if;
else
-- Go back to the uninitialized state.
stateNext <= STATE_UNINITIALIZED;
end if;
when STATE_NORMAL =>
-------------------------------------------------------------------
-- This state is the normal state. It relays frames and handle flow
-- control.
-------------------------------------------------------------------
-- Check that both the port and link is initialized.
if (portInitialized_i = '1') and (linkInitialized_i = '1') then
-- The port and link is initialized.
-- There has been no timeout.
-- Check if any control symbol has been received from the link
-- partner.
952,58 → 1061,87
case txControlStype0 is
when STYPE0_STATUS =>
-- Save the number of buffers in the link partner.
bufferStatusNext <= txControlParameter1;
if (outputErrorStopped_i = '0') then
-- Save the number of buffers in the link partner.
bufferStatus_o <= txControlParameter1;
end if;
when STYPE0_PACKET_ACCEPTED =>
-- The link partner is accepting a frame.
 
-- Save the number of buffers in the link partner.
bufferStatusNext <= txControlParameter1;
-- Check if expecting this type of reply and that the ackId is
-- expected.
if ((ackIdCurrent /= ackIdWindowCurrent) and
(ackIdCurrent = unsigned(txControlParameter0))) then
-- The packet-accepted is expected and the ackId is the expected.
-- The frame has been accepted by the link partner.
 
-- Update to a new buffer and increment the ackId.
readFrame_o <= '1';
ackIdNext <= ackIdCurrent + 1;
else
-- Unexpected packet-accepted or packet-accepted for
-- unexpected ackId.
counterNext <= NUMBER_LINK_RESPONSE_RETRIES;
stateNext <= STATE_SEND_LINK_REQUEST;
if (outputErrorStopped_i = '0') then
-- Save the number of buffers in the link partner.
bufferStatus_o <= txControlParameter1;
-- Check if expecting this type of reply and that the ackId is
-- expected.
if ((ackId_i /= ackIdWindow_i) and
(ackId_i = txControlParameter0)) then
-- The packet-accepted is expected and the ackId is the expected.
-- The frame has been accepted by the link partner.
-- Update to a new buffer and increment the ackId.
readFrame_o <= '1';
ackId_o <= std_logic_vector(unsigned(ackId_i) + 1);
else
-- Unexpected packet-accepted or packet-accepted for
-- unexpected ackId.
sendLinkRequestOut <= '1';
numberSentLinkRequests_o <= NUMBER_LINK_RESPONSE_RETRIES;
outputErrorStopped_o <= '1';
end if;
end if;
when STYPE0_PACKET_RETRY =>
-- The link partner has asked for a frame retransmission.
 
-- Save the number of buffers in the link partner.
bufferStatusNext <= txControlParameter1;
if (outputErrorStopped_i = '0') then
-- Save the number of buffers in the link partner.
bufferStatus_o <= txControlParameter1;
 
-- Check if the ackId is the one expected.
if (ackIdCurrent = unsigned(txControlParameter0)) then
-- The ackId to retry is expected.
-- Go to the output-retry-stopped state.
stateNext <= STATE_OUTPUT_RETRY_STOPPED;
else
-- Unexpected ackId to retry.
counterNext <= NUMBER_LINK_RESPONSE_RETRIES;
stateNext <= STATE_SEND_LINK_REQUEST;
-- Check if the ackId is the one expected.
if (ackId_i = txControlParameter0) then
-- The ackId to retry is expected.
-- Go to the output-retry-stopped state.
-- REMARK: The output-retry-stopped state is equivalent
-- to sending a restart-from-retry.
sendRestartFromRetryOut <= '1';
else
-- Unexpected ackId to retry.
sendLinkRequestOut <= '1';
numberSentLinkRequests_o <= NUMBER_LINK_RESPONSE_RETRIES;
outputErrorStopped_o <= '1';
end if;
end if;
 
when STYPE0_PACKET_NOT_ACCEPTED =>
-- Packet was rejected by the link-partner.
-- REMARK: Indicate that this has happened to the outside...
counterNext <= NUMBER_LINK_RESPONSE_RETRIES;
stateNext <= STATE_SEND_LINK_REQUEST;
if (outputErrorStopped_i = '0') then
-- Packet was rejected by the link-partner.
sendLinkRequestOut <= '1';
numberSentLinkRequests_o <= NUMBER_LINK_RESPONSE_RETRIES;
outputErrorStopped_o <= '1';
end if;
when STYPE0_LINK_RESPONSE =>
-- Dont expect or need a link-response in this state.
-- Discard it.
if (outputErrorStopped_i = '1') then
-- Check if the link partner return value is acceptable.
if ((unsigned(txControlParameter0) - unsigned(ackId_i)) <=
(unsigned(ackIdWindow_i) - unsigned(ackId_i))) then
-- Recoverable error.
-- Use the received ackId and recover by removing packets
-- that has been received by the link-partner.
recoverCounter_o <= txControlParameter0;
recoverActive_o <= '1';
else
-- Totally out of sync.
-- REMARK: What to do here???
--readWindowReset_o <= '1';
--stateNext <= STATE_UNINITIALIZED;
end if;
else
-- Dont expect or need a link-response in this state.
-- Discard it.
end if;
when STYPE0_VC_STATUS =>
-- Not supported.
1022,534 → 1160,527
end case;
 
-- Indicate the control symbol has been processed.
txControlUpdate_o <= '1';
else
-- No control symbol has been received.
-- Check if the oldest frame timeout has expired.
if ((ackIdCurrent /= ackIdWindowCurrent) and
(timeoutExpired = '1')) then
-- There has been a timeout on a transmitted frame.
-- Send link-request.
counterNext <= NUMBER_LINK_RESPONSE_RETRIES;
stateNext <= STATE_SEND_LINK_REQUEST;
else
-- There has been no timeout.
-- Check if the outbound fifo needs new data.
if (txFull_i = '0') then
-- There is room available in the outbound FIFO.
txControlUpdate_o <= '1';
end if;
end if;
end if;
end if;
end if;
end process;
-----------------------------------------------------------------------------
-- N-2 pipeline stage.
-- Create stype1-part of symbols and data symbols. Save the time when a
-- packet was fully sent.
-- Input: sendRestartFromRetry, sendLinkRequest
-- Output: ackIdWindow, frameState, timeout(0 to 31),
-- symbolControlStart, symbolControlEnd, symbolControlRestart,
-- symbolControlLinkRequest, symbolData2, symbolData2Content.
-----------------------------------------------------------------------------
 
-- Check if there are any events from the receiver.
if (rxControlEmpty_i = '0') then
-- A symbol from the receiver should be transmitted.
process(clk, areset_n)
begin
if (areset_n = '0') then
symbolControlRestart <= '0';
symbolControlLinkRequest <= '0';
symbolControlStart <= '0';
symbolControlEnd <= '0';
symbolData <= '0';
symbolDataContent <= (others => '0');
elsif (clk'event and clk = '1') then
symbolControlRestart <= symbolControlRestartOut;
symbolControlLinkRequest <= symbolControlLinkRequestOut;
symbolControlStart <= symbolControlStartOut;
symbolControlEnd <= symbolControlEndOut;
symbolData <= symbolDataOut;
symbolDataContent <= symbolDataContentOut;
end if;
end process;
-- This process decide which stype1-part of a control symbols to send as well
-- as all data symbols.
process(frameState_i, ackIdWindow_i, timeCurrent_i, sendRestartFromRetry, sendLinkRequest)
begin
readFrame_o <= '0';
readFrameRestart_o <= '0';
readWindowReset_o <= '0';
readWindowNext_o <= '0';
readContent_o <= '0';
 
-- Send the receiver symbol and a NOP.
-- REMARK: Combine this symbol with an STYPE1 to more effectivly
-- utilize the link.
symbolWrite <= '1';
symbolType <= SYMBOL_CONTROL;
stype0 <= rxControlStype0;
parameter0 <= rxControlParameter0;
parameter1 <= rxControlParameter1;
stype1 <= STYPE1_NOP;
cmd <= "000";
frameState_o <= frameState_i;
ackIdWindow_o <= ackIdWindow_i;
timeSentWrite_o <= '0';
timeSentWriteAddress_o <= ackIdWindow_i;
timeSentWriteData_o <= timeCurrent_i;
 
-- Remove the symbol from the fifo.
rxControlUpdate_o <= '1';
symbolControlRestartOut <= '0';
symbolControlLinkRequestOut <= '0';
symbolControlStartOut <= '0';
symbolControlEndOut <= '0';
symbolDataOut <= '0';
symbolDataContentOut <= (others => '0');
 
-- Check if the transmitted symbol contains status about
-- available buffers.
if ((rxControlStype0 = STYPE0_PACKET_ACCEPTED) or
(rxControlStype0 = STYPE0_PACKET_RETRY)) then
-- A symbol containing the bufferStatus has been sent.
symbolsTransmittedNext <= 0;
else
-- A symbol not containing the bufferStatus has been sent.
-- REMARK: symbolsTransmitted might overflow...
symbolsTransmittedNext <= symbolsTransmittedCurrent + 1;
end if;
else
-- No events from the receiver.
if (recoverActive_i = '1') then
-- REMARK: Make sure idle is generated when this state is active...
ackIdWindow_o <= recoverCounter_i;
frameState_o <= FRAME_START;
 
-- Check if a status symbol must be sent.
if (symbolsTransmittedCurrent = 255) then
-- A status symbol must be sent.
-- Reset the number of transmitted symbols between statuses.
symbolsTransmittedNext <= 0;
-- Send status.
symbolWrite <= '1';
symbolType <= SYMBOL_CONTROL;
stype0 <= STYPE0_STATUS;
parameter0 <= ackIdStatus_i;
parameter1 <= "11111";
stype1 <= STYPE1_NOP;
cmd <= "000";
else
-- A status symbol does not have to be sent.
-- Check if a frame transfer is in progress.
case frameStateCurrent is
when FRAME_START =>
---------------------------------------------------------------
-- No frame has been started.
---------------------------------------------------------------
 
-- Wait for a new frame to arrive from the frame buffer,
-- for new buffers to be available at the link-partner
-- and also check that a maximum 31 frames are outstanding.
if ((readWindowEmpty_i = '0') and (bufferStatusCurrent /= "00000") and
((ackIdWindowCurrent - ackIdCurrent) /= 31)) then
-- New data is available for transmission and there
-- is room to receive it at the other side.
-- Indicate that a control symbol has been sent to start the
-- transmission of the frame.
frameStateNext <= FRAME_CHECK;
 
-- Update the output from the frame buffer to contain the
-- data when it is read later.
readContent_o <= '1';
else
-- There are no frame data to send or the link partner has
-- no available buffers.
-- Send idle-sequence.
symbolWrite <= '1';
symbolType <= SYMBOL_IDLE;
 
-- A symbol not containing the buffer status has been sent.
symbolsTransmittedNext <= symbolsTransmittedCurrent + 1;
end if;
 
when FRAME_CHECK =>
-------------------------------------------------------
-- Check if we are allowed to transmit this packet.
-------------------------------------------------------
-- Check if this packet is allowed to be transmitted.
if ((portEnable_i = '1') or (readContentData_i(19 downto 16) = FTYPE_MAINTENANCE_CLASS)) then
-- The packet may be transmitted.
-- Indicate that a control symbol has been sent to start the
-- transmission of the frame.
frameStateNext <= FRAME_ACKID;
-- Send a control symbol to start the packet and a status to complete
-- the symbol.
symbolWrite <= '1';
symbolType <= SYMBOL_CONTROL;
stype0 <= STYPE0_STATUS;
parameter0 <= ackIdStatus_i;
parameter1 <= "11111";
stype1 <= STYPE1_START_OF_PACKET;
cmd <= "000";
 
-- A symbol containing the bufferStatus has been sent.
symbolsTransmittedNext <= 0;
else
-- The packet should be discarded.
 
-- Check that there are no outstanding packets that
-- has not been acknowledged.
if(ackIdWindowCurrent /= ackIdCurrent) then
-- There are packets that has not been acknowledged.
-- Send idle-sequence.
symbolWrite <= '1';
symbolType <= SYMBOL_IDLE;
 
-- A symbol not containing the buffer status has been sent.
symbolsTransmittedNext <= symbolsTransmittedCurrent + 1;
else
-- No unacknowledged packets.
-- It is now safe to remove the unallowed frame.
readFrame_o <= '1';
 
-- Go back and send a new frame.
frameStateNext <= FRAME_START;
end if;
end if;
when FRAME_ACKID =>
---------------------------------------------------------------
-- Send the first packet content containing our current
-- ackId.
---------------------------------------------------------------
 
-- Write a new data symbol and fill in our ackId on the
-- packet.
symbolWrite <= '1';
symbolType <= SYMBOL_DATA;
symbolData <= std_logic_vector(ackIdWindowCurrent) & "0" & readContentData_i(25 downto 0);
 
-- Continue to send the rest of the body of the packet.
readContent_o <= '1';
frameStateNext <= FRAME_BODY;
-- A symbol not containing the buffer status has been sent.
symbolsTransmittedNext <= symbolsTransmittedCurrent + 1;
when FRAME_BODY =>
---------------------------------------------------------------
-- The frame has not been fully sent.
-- Send a data symbol.
---------------------------------------------------------------
-- REMARK: Add support for partial frames...
-- Check if the frame is ending.
if (readContentEnd_i = '0') then
-- The frame is not ending.
 
-- Write a new data symbol.
symbolWrite <= '1';
symbolType <= SYMBOL_DATA;
symbolData <= readContentData_i;
 
-- Continue to send the rest of the body of the packet.
readContent_o <= '1';
 
-- A symbol not containing the buffer status has been sent.
symbolsTransmittedNext <= symbolsTransmittedCurrent + 1;
else
-- The frame is ending.
 
-- Update the window to the next frame.
-- It takes one tick for the output from the frame
-- buffer to get updated.
readWindowNext_o <= '1';
 
-- Proceed to check if there is another frame to start
-- with directly.
frameStateNext <= FRAME_END;
end if;
when FRAME_END =>
---------------------------------------------------------------
-- A frame has ended and the window has been updated.
-- Check if the next symbol should end the frame or if a
-- new one should be started.
---------------------------------------------------------------
 
-- Check if there is a new frame pending.
if (readWindowEmpty_i = '1') then
-- No new frame is pending.
-- Send a control symbol to end the packet.
symbolWrite <= '1';
symbolType <= SYMBOL_CONTROL;
stype0 <= STYPE0_STATUS;
parameter0 <= ackIdStatus_i;
parameter1 <= "11111";
stype1 <= STYPE1_END_OF_PACKET;
cmd <= "000";
-- A symbol containing the bufferStatus has been sent.
symbolsTransmittedNext <= 0;
end if;
 
-- Update the window ackId.
ackIdWindowNext <= ackIdWindowCurrent + 1;
 
-- Start timeout supervision for transmitted frame.
timeoutWrite <= '1';
timeoutAddress <= std_logic_vector(ackIdWindowCurrent);
 
-- Start a new frame the next time.
frameStateNext <= FRAME_START;
when others =>
---------------------------------------------------------------
--
---------------------------------------------------------------
null;
end case;
end if;
end if;
else
-- Wait for new storage in the transmission FIFO to become
-- available.
-- Dont do anything.
end if;
end if;
end if;
else
-- The port or the link has become uninitialized.
-- Go back to the uninitialized state.
stateNext <= STATE_UNINITIALIZED;
end if;
 
when STATE_OUTPUT_RETRY_STOPPED =>
if (ackId_i /= recoverCounter_i) then
readFrame_o <= '1';
else
readWindowReset_o <= '1';
end if;
else
if (txFull_i = '0') then
if (operational_i = '0') then
-----------------------------------------------------------------------
-- This is the output-retry-stopped state described in 5.9.1.5.
-- This state is entered at startup. A port that is not initialized
-- should only transmit idle sequences.
-----------------------------------------------------------------------
 
-- Check if the outbound fifo needs new data.
if (txFull_i = '0') then
-- There is room available in the outbound FIFO.
 
-- Initialize framing before entering the operational state.
-- REMARK: Only do this when the portInitialized becomes asserted???
frameState_o <= FRAME_START;
ackIdWindow_o <= ackId_i;
readWindowReset_o <= '1';
else
-------------------------------------------------------------------
-- This state is the operational state. It relays frames and handle
-- flow control.
-------------------------------------------------------------------
if (sendRestartFromRetry = '1') then
-- Send a restart-from-retry control symbol to acknowledge the restart
-- of the frame.
symbolWrite <= '1';
symbolType <= SYMBOL_CONTROL;
stype0 <= STYPE0_STATUS;
parameter0 <= ackIdStatus_i;
parameter1 <= "11111";
stype1 <= STYPE1_RESTART_FROM_RETRY;
cmd <= "000";
symbolControlRestartOut <= '1';
 
-- Make sure there wont be any timeout before the frame is
-- starting to be retransmitted.
timeoutWrite <= '1';
timeoutAddress <= std_logic_vector(ackIdCurrent);
timeSentWrite_o <= '1';
 
-- Restart the frame transmission.
ackIdWindowNext <= ackIdCurrent;
frameStateNext <= FRAME_START;
ackIdWindow_o <= ackId_i;
frameState_o <= FRAME_START;
readWindowReset_o <= '1';
end if;
 
-- Proceed back to the normal state.
stateNext <= STATE_NORMAL;
-- A symbol containing the bufferStatus has been sent.
symbolsTransmittedNext <= 0;
end if;
when STATE_SEND_LINK_REQUEST =>
-----------------------------------------------------------------------
-- Send a link-request symbol when the transmission fifo is ready. Then
-- always proceed to the output-error-state.
-----------------------------------------------------------------------
-- Check if the outbound fifo needs new data.
if (txFull_i = '0') then
-- There is room available in the outbound FIFO.
if (sendLinkRequest = '1') then
-- Dont restart the packet transmission since we do not yet know which
-- packets that was successfully received by our link partner.
 
-- Send a link-request symbol.
symbolWrite <= '1';
symbolType <= SYMBOL_CONTROL;
stype0 <= STYPE0_STATUS;
parameter0 <= ackIdStatus_i;
parameter1 <= "11111";
stype1 <= STYPE1_LINK_REQUEST;
cmd <= LINK_REQUEST_CMD_INPUT_STATUS;
symbolControlLinkRequestOut <= '1';
 
-- Write the current timer value.
timeoutWrite <= '1';
timeoutAddress <= std_logic_vector(ackIdCurrent);
-- Proceed to the output-error-stopped state.
stateNext <= STATE_OUTPUT_ERROR_STOPPED;
-- A symbol containing the bufferStatus has been sent.
symbolsTransmittedNext <= 0;
timeSentWrite_o <= '1';
end if;
when STATE_OUTPUT_ERROR_STOPPED =>
-------------------------------------------------------------------
-- This state is the error stopped state described in 5.13.2.7.
-------------------------------------------------------------------
-- Check that both the port and link is initialized.
if (portInitialized_i = '1') and (linkInitialized_i = '1') then
-- The port and link is initialized.
-- Check if any control symbol has been received from the link
-- partner.
if (txControlEmpty_i = '0') then
-- A control symbol has been received.
if ((sendRestartFromRetry = '0') and (sendLinkRequest = '0') and
(outputErrorStopped_i = '0')) then
-- Check if a frame transfer is in progress.
-- REMARK: Hold any data symbol if there is a pending symbol from the
-- receiver side...
 
-- Check the received control symbol.
case txControlStype0 is
when STYPE0_PACKET_ACCEPTED =>
-- Wait for a link-response.
-- Discard these.
case frameState_i is
when FRAME_START =>
---------------------------------------------------------------
-- No frame has been started.
---------------------------------------------------------------
 
when STYPE0_PACKET_RETRY =>
-- Wait for a link-response.
-- Discard these.
-- Wait for a new frame to arrive from the frame buffer,
-- for new buffers to be available at the link-partner
-- and also check that a maximum 31 frames are outstanding.
-- REMARK: Only update readContent_o in the last instance
-- if cascaded...
if ((readWindowEmpty_i = '0') and
(bufferStatus_i /= "00000") and
((unsigned(ackIdWindow_i) - unsigned(ackId_i)) /= 31)) then
-- New data is available for transmission and there
-- is room to receive it at the other side.
when STYPE0_PACKET_NOT_ACCEPTED =>
-- Wait for a link-response.
-- Discard these.
-- Indicate that a control symbol has been sent to start the
-- transmission of the frame.
frameState_o <= FRAME_CHECK;
 
when STYPE0_STATUS =>
-- Wait for a link-response.
-- Discard these.
-- Update the output from the frame buffer to contain the
-- data when it is read later.
readContent_o <= '1';
end if;
 
when FRAME_CHECK =>
-------------------------------------------------------
-- Check if we are allowed to transmit this packet.
-------------------------------------------------------
-- Check if this packet is allowed to be transmitted.
if ((portEnable_i = '1') or
(readContentData_i(19 downto 16) = FTYPE_MAINTENANCE_CLASS)) then
-- The packet may be transmitted.
when STYPE0_LINK_RESPONSE =>
-- Check if the link partner return value is acceptable.
if ((unsigned(txControlParameter0) - ackIdCurrent) <=
(ackIdWindowCurrent - ackIdCurrent)) then
-- Recoverable error.
-- Use the received ackId and recover by removing packets
-- that were received by the link-partner.
ackIdWindowNext <= unsigned(txControlParameter0);
stateNext <= STATE_RECOVER;
else
-- Totally out of sync.
stateNext <= STATE_FATAL_ERROR;
end if;
-- Indicate that a control symbol has been sent to start the
-- transmission of the frame.
frameState_o <= FRAME_ACKID;
frameWordCounter_o <= readContentWords_i;
frameContent_o <= readContentData_i;
when STYPE0_VC_STATUS =>
-- Not supported.
when STYPE0_RESERVED =>
-- Not supported.
-- Send a control symbol to start the packet and a status to
-- complete the symbol.
symbolControlStartOut <= '1';
else
-- The packet should be discarded.
-- Send idle-sequence.
 
when STYPE0_IMPLEMENTATION_DEFINED =>
-- Not supported.
when others =>
null;
end case;
-- Check that there are no outstanding packets that
-- has not been acknowledged.
if(unsigned(ackIdWindow_i) = unsigned(ackId_i)) then
-- No unacknowledged packets.
-- It is now safe to remove the unallowed frame.
readFrame_o <= '1';
 
-- Indicate the control symbol has been processed.
txControlUpdate_o <= '1';
else
-- No control symbol has been received.
-- Check if the timeout for a link-response has expired.
if (timeoutExpired = '1') then
-- There was no reply on the link-request.
-- Go back and send a new frame.
frameState_o <= FRAME_START;
end if;
end if;
-- Count the number of retransmissions and abort if
-- no reply has been received for too many times.
if (counterCurrent /= 0) then
-- Not sent link-request too many times.
-- Send another link-request.
counterNext <= counterCurrent - 1;
stateNext <= STATE_SEND_LINK_REQUEST;
when FRAME_ACKID =>
---------------------------------------------------------------
-- Send the first packet content containing our current
-- ackId.
---------------------------------------------------------------
 
-- Write a new data symbol and fill in our ackId on the
-- packet.
symbolDataOut <= '1';
symbolDataContentOut <=
std_logic_vector(ackIdWindow_i) & "0" &
frameContent_i((32*NUMBER_WORDS)-1 downto (32*(NUMBER_WORDS-1))-1);
 
if (unsigned(frameWordCounter_i) /= 0) then
frameWordCounter_o <=
std_logic_vector(unsigned(frameWordCounter_i) - 1);
frameContent_o <=
frameContent_i((32*(NUMBER_WORDS-1))-1 downto 0) & x"0000";
else
-- No response for too many times.
stateNext <= STATE_FATAL_ERROR;
readContent_o <= '1';
frameWordCounter_o <= readContentWords_i;
frameContent_o <= readContentData_i;
end if;
else
-- There has been no timeout.
-- Check if the outbound fifo needs new data.
if (txFull_i = '0') then
-- There is room available in the outbound FIFO.
-- Continue to send the rest of the body of the packet.
frameState_o <= FRAME_BODY;
when FRAME_BODY =>
---------------------------------------------------------------
-- The frame has not been fully sent.
-- Send a data symbol.
---------------------------------------------------------------
-- REMARK: There will be idle symbols generated here if the
-- end-of-packet cannot be generated directly following the last
-- data symbol... need to rewrite PacketBufferWindow to indicate
-- the end at the last word.
-- REMARK: Dont send anything if there is a pending symbol in the
-- rx-control fifo to let it be transmitted in the middle of the
-- packet...
-- Write a new data symbol.
symbolDataOut <= '1';
symbolDataContentOut <=
frameContent_i((32*NUMBER_WORDS)-1 downto (32*(NUMBER_WORDS-1))-1);
 
-- Check if there are any events from the receiver.
if (rxControlEmpty_i = '0') then
-- A symbol from the receiver should be transmitted.
if (unsigned(frameWordCounter_i) /= 0) then
frameWordCounter_o <=
std_logic_vector(unsigned(frameWordCounter_i) - 1);
frameContent_o <=
frameContent_i((32*(NUMBER_WORDS-1))-1 downto 0) & x"0000";
else
-- Check if the frame is ending.
if (readContentEnd_i = '1') then
-- The frame is ending.
 
-- Send the receiver symbol and a NOP.
symbolWrite <= '1';
symbolType <= SYMBOL_CONTROL;
stype0 <= rxControlStype0;
parameter0 <= rxControlParameter0;
parameter1 <= rxControlParameter1;
stype1 <= STYPE1_NOP;
cmd <= "000";
-- Update the window to the next frame.
-- It takes one tick for the output from the frame
-- buffer to get updated.
readWindowNext_o <= '1';
 
-- Remove the symbol from the fifo.
rxControlUpdate_o <= '1';
 
-- Check if the transmitted symbol contains status about
-- available buffers.
-- The receiver never send any status so that does not have
-- to be checked.
if ((rxControlStype0 = STYPE0_PACKET_ACCEPTED) or
(rxControlStype0 = STYPE0_PACKET_RETRY)) then
-- A symbol containing the bufferStatus has been sent.
symbolsTransmittedNext <= 0;
else
-- A symbol not containing the buffer status has been sent.
symbolsTransmittedNext <= symbolsTransmittedCurrent + 1;
end if;
-- Proceed to check if there is another frame to start
-- with directly.
frameState_o <= FRAME_END;
else
-- No events from the receiver.
-- There are no frame data to send or the link partner has
-- no available buffers.
 
-- Check if a status symbol must be sent.
if (symbolsTransmittedCurrent = 255) then
-- A status symbol must be sent.
-- Reset the number of transmitted symbols between statuses.
symbolsTransmittedNext <= 0;
-- Send status.
symbolWrite <= '1';
symbolType <= SYMBOL_CONTROL;
stype0 <= STYPE0_STATUS;
parameter0 <= ackIdStatus_i;
parameter1 <= "11111";
stype1 <= STYPE1_NOP;
cmd <= "000";
else
-- A status symbol does not have to be sent.
-- Send idle-sequence.
symbolWrite <= '1';
symbolType <= SYMBOL_IDLE;
-- A symbol not containing the buffer status has been sent.
symbolsTransmittedNext <= symbolsTransmittedCurrent + 1;
end if;
readContent_o <= '1';
frameWordCounter_o <= readContentWords_i;
frameContent_o <= readContentData_i;
end if;
else
-- Wait for new storage in the transmission FIFO to become
-- available.
-- Dont do anything.
end if;
end if;
when FRAME_END =>
---------------------------------------------------------------
-- A frame has ended and the window has been updated.
-- Check if the next symbol should end the frame or if a
-- new one should be started.
---------------------------------------------------------------
 
-- Check if there is a new frame pending.
if (readWindowEmpty_i = '1') then
-- No new frame is pending.
-- Send a control symbol to end the packet.
symbolControlEndOut <= '1';
end if;
 
-- Update the window ackId.
ackIdWindow_o <= std_logic_vector(unsigned(ackIdWindow_i) + 1);
 
-- Start timeout supervision for transmitted frame.
timeSentWrite_o <= '1';
 
-- Start a new frame the next time.
frameState_o <= FRAME_START;
when others =>
---------------------------------------------------------------
--
---------------------------------------------------------------
null;
end case;
end if;
end if;
end if;
end if;
end process;
 
-----------------------------------------------------------------------------
-- N-1
-- Create the stype0 and stype1 part of a control symbol.
-- This process makes sure that the buffer status are transmitted at least
-- every 255 symbol.
-- At startup it makes sure that at least 16 status symbols are transmitted
-- before the operational-state is entered.
-- Input: symbolControlStart, symbolControlEnd, symbolControlRestart,
-- symbolControlLinkRequest, symbolData, symbolDataContent
-- Output: symbolsTransmitted_o, operational_o,
-- symbolControl, stype0, parameter0, parameter1, stype1, cmd,
-- symbolData1, symbolData1Content
-----------------------------------------------------------------------------
 
process(clk, areset_n)
begin
if (areset_n = '0') then
controlValid <= '0';
stype0 <= (others=>'0');
parameter0 <= (others=>'0');
parameter1 <= (others=>'0');
stype1 <= STYPE1_NOP;
cmd <= (others=>'0');
dataValid <= '0';
dataContent <= (others=>'0');
elsif (clk'event and clk = '1') then
if (txFull_i = '0') then
controlValid <= controlValidOut;
stype0 <= stype0Out;
parameter0 <= parameter0Out;
parameter1 <= parameter1Out;
stype1 <= STYPE1_NOP;
cmd <= "000";
dataValid <= symbolData;
dataContent <= symbolDataContent;
if (symbolControlStart = '1') then
stype1 <= STYPE1_START_OF_PACKET;
end if;
if (symbolControlEnd = '1') then
stype1 <= STYPE1_END_OF_PACKET;
end if;
if (symbolControlRestart = '1') then
stype1 <= STYPE1_RESTART_FROM_RETRY;
end if;
if (symbolControlLinkRequest = '1') then
stype1 <= STYPE1_LINK_REQUEST;
cmd <= LINK_REQUEST_CMD_INPUT_STATUS;
end if;
end if;
end if;
end process;
 
symbolControlStype1 <=
symbolControlRestart or symbolControlLinkRequest or
symbolControlStart or symbolControlEnd;
process(txFull_i, linkInitialized_i, ackIdStatus_i, portInitialized_i,
operational_i, counter_i, statusReceived_i, symbolsTransmitted_i)
begin
operational_o <= operational_i;
counter_o <= counter_i;
controlValidOut <= '0';
stype0Out <= STYPE0_STATUS;
parameter0Out <= ackIdStatus_i;
parameter1Out <= "11111";
-- Check if there is room for more in the outbound fifo.
if (txFull_i = '0') then
-- The outbound fifo needs to be filled.
 
-- Check the operational state.
if (operational_i = '0') then
-----------------------------------------------------------------------
-- This state is entered at startup. A port that is not initialized
-- should only transmit idle sequences.
-----------------------------------------------------------------------
-- Check if the port is initialized.
if (portInitialized_i = '1') then
---------------------------------------------------------------------
-- The specification requires a status control symbol being sent at
-- least every 1024 code word until an error-free status has been
-- received. This implies that at most 256 idle sequences should be
-- sent in between status control symbols. Once an error-free status
-- has been received, status symbols may be sent more rapidly. At
-- least 15 statuses has to be transmitted once an error-free status
-- has been received.
---------------------------------------------------------------------
 
-- Check if we are ready to change state to operational.
if ((linkInitialized_i = '1') and
(unsigned(counter_i) = 0)) then
-- Receiver has received enough error free status symbols and we
-- have transmitted enough.
-- Considder ourselfs operational.
operational_o <= '1';
else
-- Not ready to change state to operational.
-- Dont do anything.
end if;
-- Check if idle sequence or a status symbol should be transmitted.
if (((statusReceived_i = '0') and (symbolsTransmitted_i = x"ff")) or
((statusReceived_i = '1') and (symbolsTransmitted_i > x"0f"))) then
-- A status symbol should be transmitted.
-- Send a status control symbol to the link partner.
controlValidOut <= '1';
 
-- Reset idle sequence transmission counter.
symbolsTransmitted_o <= (others=>'0');
 
-- Check if the number of transmitted statuses should be updated.
if (statusReceived_i = '1') and (unsigned(counter_i) /= 0) then
counter_o <= std_logic_vector(unsigned(counter_i) - 1);
end if;
else
-- The port or the link has become uninitialized.
-- Go back to the uninitialized state.
stateNext <= STATE_UNINITIALIZED;
-- Increment the idle sequence transmission counter.
symbolsTransmitted_o <= std_logic_vector(unsigned(symbolsTransmitted_i) + 1);
end if;
else
-- The port is not initialized.
-- Reset initialization variables.
counter_o <= NUMBER_STATUS_TRANSMIT;
end if;
else
---------------------------------------------------------------------
-- This is the operational state.
-- It is entered once the link has been considdered up and running.
---------------------------------------------------------------------
 
when STATE_RECOVER =>
-----------------------------------------------------------------------
-- A recoverable error condition has occurred.
-- When this state is entered, ackIdWindow should contain the ackId to
-- proceed with.
-----------------------------------------------------------------------
-- Check if the port is still initialized.
if (portInitialized_i = '1') then
-- The port is still initialized.
-- Check if a status must be sent.
-- A status must be sent when there are not other stype0 value to
-- send or if too many symbols without buffer-status has been sent.
-- REMARK: Is there a risk of a race when a generated status-symbol
-- is sent before another symbol stored in the rx-control fifo???
if (((symbolControlStype1 = '1') and (rxControlEmpty_i = '1')) or
((symbolControlStype1 = '0') and (symbolData = '0') and
(symbolsTransmitted_i = x"ff"))) then
-- A control symbol is about to be sent without pending symbol from
-- receiver or too many idle symbols has been sent.
 
-- Check if the expected ackId has incremented enough.
if (ackIdCurrent /= ackIdWindowCurrent) then
-- Remove this frame. It has been received by the link-partner.
readFrame_o <= '1';
ackIdNext <= ackIdCurrent + 1;
-- Force the sending of a status containing the bufferStatus.
controlValidOut <= '1';
symbolsTransmitted_o <= (others=>'0');
elsif ((symbolControlStype1 = '1') and (rxControlEmpty_i = '0')) then
-- A control symbol is about to be sent and there is a pending
-- symbol from the receiver.
-- Remove the symbol from the fifo.
rxControlUpdate_o <= '1';
-- Send the receiver symbol.
controlValidOut <= '1';
stype0Out <= rxControlStype0;
parameter0Out <= rxControlParameter0;
parameter1Out <= rxControlParameter1;
-- Check if the transmitted symbol contains status about
-- available buffers.
if ((rxControlStype0 = STYPE0_PACKET_ACCEPTED) or
(rxControlStype0 = STYPE0_PACKET_RETRY)) then
-- A symbol containing the bufferStatus has been sent.
symbolsTransmitted_o <= (others=>'0');
else
-- A symbol not containing the bufferStatus has been sent.
symbolsTransmitted_o <= std_logic_vector(unsigned(symbolsTransmitted_i) + 1);
end if;
else
-- Keep this frame.
-- Restart the window and the frame transmission.
frameStateNext <= FRAME_START;
readWindowReset_o <= '1';
stateNext <= STATE_NORMAL;
-- A symbol not containing the bufferStatus has been sent.
controlValidOut <= '0';
symbolsTransmitted_o <= std_logic_vector(unsigned(symbolsTransmitted_i) + 1);
end if;
else
-- The port is not initialized anymore.
-- Change the operational state.
operational_o <= '0';
end if;
end if;
end if;
end process;
-----------------------------------------------------------------------------
-- N pipeline stage.
-- Make all symbols ready for transmission, i.e. calculate the CRC5 on
-- control symbols.
-- Inputs: controlValid, stype0, parameter0, parameter1, stype1, cmd,
-- symbolData1, symbolData1Content
-----------------------------------------------------------------------------
 
when STATE_FATAL_ERROR =>
-----------------------------------------------------------------------
-- A fatal error condition has occurred.
-----------------------------------------------------------------------
controlContent(31 downto 29) <= stype0;
controlContent(28 downto 24) <= parameter0;
controlContent(23 downto 19) <= parameter1;
controlContent(18 downto 16) <= stype1;
controlContent(15 downto 13) <= cmd;
controlContent(12 downto 8) <= crc5;
controlContent(7 downto 0) <= x"00";
 
-- Reset the window and resynchronize the link.
-- REMARK: Count these situations...
-- REMARK: Do something else here???
readWindowReset_o <= '1';
stateNext <= STATE_UNINITIALIZED;
when others =>
-------------------------------------------------------------------
--
-------------------------------------------------------------------
null;
end case;
Crc5Calculator: Crc5ITU
port map(
d_i=>controlContent(31 downto 13), crc_o=>crc5);
 
txWrite_o <= not txFull_i;
process(clk, areset_n)
begin
if (areset_n = '0') then
txType_o <= SYMBOL_IDLE;
txData_o <= (others=>'0');
elsif (clk'event and clk = '1') then
if (txFull_i = '0') then
txType_o <= SYMBOL_IDLE;
if (controlValid = '1') then
txType_o <= SYMBOL_CONTROL;
txData_o <= controlContent;
end if;
if (dataValid = '1') then
txType_o <= SYMBOL_DATA;
txData_o <= dataContent;
end if;
end if;
end if;
end process;
 
end process;
end architecture;
 
 
1563,10 → 1694,259
use work.rio_common.all;
 
 
entity RioReceiver is
generic(
NUMBER_WORDS : natural range 1 to 4 := 1);
port(
clk : in std_logic;
areset_n : in std_logic;
portEnable_i : in std_logic;
localAckIdWrite_i : in std_logic;
inboundAckId_i : in std_logic_vector(4 downto 0);
inboundAckId_o : out std_logic_vector(4 downto 0);
portInitialized_i : in std_logic;
rxEmpty_i : in std_logic;
rxRead_o : out std_logic;
rxType_i : in std_logic_vector(2*NUMBER_WORDS-1 downto 0);
rxData_i : in std_logic_vector(32*NUMBER_WORDS-1 downto 0);
txControlWrite_o : out std_logic_vector(NUMBER_WORDS-1 downto 0);
txControlSymbol_o : out std_logic_vector(12*NUMBER_WORDS downto 0);
rxControlWrite_o : out std_logic_vector(NUMBER_WORDS-1 downto 0);
rxControlSymbol_o : out std_logic_vector(12*NUMBER_WORDS downto 0);
ackIdStatus_o : out std_logic_vector(4 downto 0);
linkInitialized_o : out std_logic;
writeFrameFull_i : in std_logic;
writeFrame_o : out std_logic;
writeFrameAbort_o : out std_logic;
writeContent_o : out std_logic;
writeContentWords_o : out std_logic_vector(1 downto 0);
writeContentData_o : out std_logic_vector(32*NUMBER_WORDS-1 downto 0));
end entity;
 
-------------------------------------------------------------------------------
--
-------------------------------------------------------------------------------
entity RioReceiver is
architecture RioReceiverImpl of RioReceiver is
 
component RioReceiverCore is
generic(
NUMBER_WORDS : natural range 1 to 4 := 1);
port(
clk : in std_logic;
areset_n : in std_logic;
 
-- Status signals used for maintenance.
portEnable_i : in std_logic;
 
-- Support for localAckIdCSR.
-- REMARK: Add support for this???
localAckIdWrite_i : in std_logic;
inboundAckId_i : in std_logic_vector(4 downto 0);
inboundAckId_o : out std_logic_vector(4 downto 0);
-- Port input interface.
portInitialized_i : in std_logic;
rxEmpty_i : in std_logic;
rxRead_o : out std_logic;
rxType_i : in std_logic_vector(1 downto 0);
rxData_i : in std_logic_vector(31 downto 0);
 
-- Receiver has received a control symbol containing:
-- packet-accepted, packet-retry, packet-not-accepted,
-- status, VC_status, link-response
txControlWrite_o : out std_logic;
txControlSymbol_o : out std_logic_vector(12 downto 0);
 
-- Reciever wants to signal the link partner:
-- a new frame has been accepted => packet-accepted(rxAckId, bufferStatus)
-- a frame needs to be retransmitted due to buffering =>
-- packet-retry(rxAckId, bufferStatus)
-- a frame is rejected due to errors => packet-not-accepted
-- a link-request should be answered => link-response
rxControlWrite_o : out std_logic;
rxControlSymbol_o : out std_logic_vector(12 downto 0);
 
-- Status signals used internally.
ackIdStatus_o : out std_logic_vector(4 downto 0);
linkInitialized_o : out std_logic;
 
-- Core->Core cascading signals.
enable_o : out std_logic;
operational_i : in std_logic;
operational_o : out std_logic;
inputRetryStopped_i : in std_logic;
inputRetryStopped_o : out std_logic;
inputErrorStopped_i : in std_logic;
inputErrorStopped_o : out std_logic;
ackId_i : in unsigned(4 downto 0);
ackId_o : out unsigned(4 downto 0);
frameIndex_i : in std_logic_vector(6 downto 0);
frameIndex_o : out std_logic_vector(6 downto 0);
frameWordCounter_i : in std_logic_vector(1 downto 0);
frameWordCounter_o : out std_logic_vector(1 downto 0);
frameContent_i : in std_logic_vector(32*NUMBER_WORDS-1 downto 0);
frameContent_o : out std_logic_vector(32*NUMBER_WORDS-1 downto 0);
crc_i : in std_logic_vector(15 downto 0);
crc_o : out std_logic_vector(15 downto 0);
-- Frame buffering interface.
writeFrameFull_i : in std_logic;
writeFrame_o : out std_logic;
writeFrameAbort_o : out std_logic;
writeContent_o : out std_logic;
writeContentWords_o : out std_logic_vector(1 downto 0);
writeContentData_o : out std_logic_vector(32*NUMBER_WORDS-1 downto 0));
end component;
 
signal enable : std_logic_vector(NUMBER_WORDS-1 downto 0);
signal operationalCurrent, operationalNext : std_logic_vector(NUMBER_WORDS-1 downto 0);
signal inputRetryStoppedCurrent, inputRetryStoppedNext : std_logic_vector(NUMBER_WORDS-1 downto 0);
signal inputErrorStoppedCurrent, inputErrorStoppedNext : std_logic_vector(NUMBER_WORDS-1 downto 0);
signal ackIdCurrent, ackIdNext : unsigned(5*NUMBER_WORDS-1 downto 0);
signal frameIndexCurrent, frameIndexNext : std_logic_vector(7*NUMBER_WORDS-1 downto 0);
signal frameWordCounterCurrent, frameWordCounterNext : std_logic_vector(2*NUMBER_WORDS-1 downto 0);
signal frameContentCurrent, frameContentNext : std_logic_vector(32*NUMBER_WORDS-1 downto 0);
signal crcCurrent, crcNext : std_logic_vector(16*NUMBER_WORDS-1 downto 0);
 
signal txControlWrite : std_logic_vector(NUMBER_WORDS-1 downto 0);
signal rxControlWrite : std_logic_vector(NUMBER_WORDS-1 downto 0);
signal writeFrame : std_logic_vector(NUMBER_WORDS-1 downto 0);
signal writeFrameAbort : std_logic_vector(NUMBER_WORDS-1 downto 0);
signal writeContent : std_logic_vector(NUMBER_WORDS-1 downto 0);
signal writeContentWords : std_logic_vector(2*NUMBER_WORDS-1 downto 0);
signal writeContentData : std_logic_vector(32*NUMBER_WORDS-1 downto 0);
 
begin
 
-----------------------------------------------------------------------------
-- Output generation to packet buffer.
-----------------------------------------------------------------------------
process(enable, writeFrame, writeFrameAbort,
writeContent, writeContentWords, writeContentData)
begin
writeFrame_o <= '0';
writeFrameAbort_o <= '0';
writeContent_o <= '0';
writeContentWords_o <= (others=>'0');
writeContentData_o <= (others=>'0');
for i in 0 to NUMBER_WORDS-1 loop
if ((writeFrame(i) = '1') and (enable(i) = '1')) then
writeFrame_o <= '1';
end if;
if ((writeFrameAbort(i) = '1') and (enable(i) = '1')) then
writeFrameAbort_o <= '1';
end if;
 
if ((writeContent(i) = '1') and (enable(i) = '1')) then
writeContent_o <= '1';
writeContentWords_o <= writeContentWords(2*(i+1)-1 downto 2*i);
writeContentData_o <= writeContentData(32*(i+1)-1 downto 32*i);
end if;
end loop;
end process;
 
-----------------------------------------------------------------------------
-- Protocol core and synchronization.
-----------------------------------------------------------------------------
process(clk, areset_n)
begin
if (areset_n = '0') then
operationalCurrent <= (others=>'0');
inputRetryStoppedCurrent <= (others=>'0');
inputErrorStoppedCurrent <= (others=>'0');
ackIdCurrent <= (others=>'0');
frameIndexCurrent <= (others => '0');
frameWordCounterCurrent <= (others=>'0');
frameContentCurrent <= (others=>'0');
crcCurrent <= (others=>'0');
elsif (clk'event and clk = '1') then
if (enable(0) = '1') then
operationalCurrent <= operationalNext;
inputRetryStoppedCurrent <= inputRetryStoppedNext;
inputErrorStoppedCurrent <= inputErrorStoppedNext;
ackIdCurrent <= ackIdNext;
frameIndexCurrent <= frameIndexNext;
frameWordCounterCurrent <= frameWordCounterNext;
frameContentCurrent <= frameContentNext;
crcCurrent <= crcNext;
end if;
end if;
end process;
 
CoreGeneration: for i in 0 to NUMBER_WORDS-1 generate
txControlWrite_o(i) <= txControlWrite(i) and enable(i);
rxControlWrite_o(i) <= rxControlWrite(i);
ReceiverCore: RioReceiverCore
generic map(NUMBER_WORDS=>NUMBER_WORDS)
port map(
clk=>clk,
areset_n=>areset_n,
portEnable_i=>portEnable_i,
localAckIdWrite_i=>localAckIdWrite_i,
inboundAckId_i=>inboundAckId_i,
inboundAckId_o=>inboundAckId_o,
portInitialized_i=>portInitialized_i,
rxEmpty_i=>rxEmpty_i,
rxRead_o=>rxRead_o,
rxType_i=>rxType_i,
rxData_i=>rxData_i,
txControlWrite_o=>txControlWrite(i),
txControlSymbol_o=>txControlSymbol_o(13*(i+1)-1 downto 13*i),
rxControlWrite_o=>rxControlWrite(i),
rxControlSymbol_o=>rxControlSymbol_o(13*(i+1)-1 downto 13*i),
ackIdStatus_o=>ackIdStatus_o,
linkInitialized_o=>linkInitialized_o,
enable_o=>enable(i),
operational_i=>operationalCurrent(i),
operational_o=>operationalNext(i),
inputRetryStopped_i=>inputRetryStoppedCurrent(i),
inputRetryStopped_o=>inputRetryStoppedNext(i),
inputErrorStopped_i=>inputErrorStoppedCurrent(i),
inputErrorStopped_o=>inputErrorStoppedNext(i),
ackId_i=>ackIdCurrent(5*(i+1)-1 downto 5*i),
ackId_o=>ackIdNext(5*(i+1)-1 downto 5*i),
frameIndex_i=>frameIndexCurrent(7*(i+1)-1 downto 7*i),
frameIndex_o=>frameIndexNext(7*(i+1)-1 downto 7*i),
frameWordCounter_i=>frameWordCounterCurrent(2*(i+1)-1 downto 2*i),
frameWordCounter_o=>frameWordCounterNext(2*(i+1)-1 downto 2*i),
frameContent_i=>frameContentCurrent(32*(i+1)-1 downto 32*i),
frameContent_o=>frameContentNext(32*(i+1)-1 downto 32*i),
crc_i=>crcCurrent(16*(i+1)-1 downto 16*i),
crc_o=>crcNext(16*(i+1)-1 downto 16*i),
writeFrameFull_i=>writeFrameFull_i,
writeFrame_o=>writeFrame(i),
writeFrameAbort_o=>writeFrameAbort(i),
writeContent_o=>writeContent(i),
writeContentWords_o=>writeContentWords(2*(i+1)-1 downto 2*i),
writeContentData_o=>writeContentData(32*(i+1)-1 downto 32*i));
end generate;
end architecture;
-------------------------------------------------------------------------------
-- RioReceiverCore
-------------------------------------------------------------------------------
library ieee;
use ieee.std_logic_1164.all;
use ieee.numeric_std.all;
use work.rio_common.all;
 
 
-------------------------------------------------------------------------------
--
-------------------------------------------------------------------------------
entity RioReceiverCore is
generic(
NUMBER_WORDS : natural range 1 to 4 := 1);
port(
clk : in std_logic;
areset_n : in std_logic;
1575,6 → 1955,7
portEnable_i : in std_logic;
 
-- Support for localAckIdCSR.
-- REMARK: Add support for this???
localAckIdWrite_i : in std_logic;
inboundAckId_i : in std_logic_vector(4 downto 0);
inboundAckId_o : out std_logic_vector(4 downto 0);
1583,7 → 1964,7
portInitialized_i : in std_logic;
rxEmpty_i : in std_logic;
rxRead_o : out std_logic;
rxControl_i : in std_logic_vector(1 downto 0);
rxType_i : in std_logic_vector(1 downto 0);
rxData_i : in std_logic_vector(31 downto 0);
 
-- Receiver has received a control symbol containing:
1605,12 → 1986,32
ackIdStatus_o : out std_logic_vector(4 downto 0);
linkInitialized_o : out std_logic;
 
-- Core->Core cascading signals.
enable_o : out std_logic;
operational_i : in std_logic;
operational_o : out std_logic;
inputRetryStopped_i : in std_logic;
inputRetryStopped_o : out std_logic;
inputErrorStopped_i : in std_logic;
inputErrorStopped_o : out std_logic;
ackId_i : in unsigned(4 downto 0);
ackId_o : out unsigned(4 downto 0);
frameIndex_i : in std_logic_vector(6 downto 0);
frameIndex_o : out std_logic_vector(6 downto 0);
frameWordCounter_i : in std_logic_vector(1 downto 0);
frameWordCounter_o : out std_logic_vector(1 downto 0);
frameContent_i : in std_logic_vector(32*NUMBER_WORDS-1 downto 0);
frameContent_o : out std_logic_vector(32*NUMBER_WORDS-1 downto 0);
crc_i : in std_logic_vector(15 downto 0);
crc_o : out std_logic_vector(15 downto 0);
-- Frame buffering interface.
writeFrameFull_i : in std_logic;
writeFrame_o : out std_logic;
writeFrameAbort_o : out std_logic;
writeContent_o : out std_logic;
writeContentData_o : out std_logic_vector(31 downto 0));
writeContentWords_o : out std_logic_vector(1 downto 0);
writeContentData_o : out std_logic_vector(32*NUMBER_WORDS-1 downto 0));
end entity;
 
 
1617,7 → 2018,7
-------------------------------------------------------------------------------
--
-------------------------------------------------------------------------------
architecture RioReceiverImpl of RioReceiver is
architecture RioReceiverCoreImpl of RioReceiverCore is
 
component Crc5ITU is
port(
1632,742 → 2033,664
crc_o : out std_logic_vector(15 downto 0));
end component;
 
type StateType is (STATE_UNINITIALIZED, STATE_PORT_INITIALIZED,
STATE_NORMAL,
STATE_INPUT_RETRY_STOPPED, STATE_INPUT_ERROR_STOPPED);
signal state : StateType;
signal statusCounter : natural range 0 to 8;
 
signal ackId : unsigned(4 downto 0);
signal frameIndex : natural range 0 to 70;
 
signal stype0 : std_logic_vector(2 downto 0);
signal parameter0 : std_logic_vector(4 downto 0);
signal parameter1 : std_logic_vector(4 downto 0);
signal stype1 : std_logic_vector(2 downto 0);
signal cmd : std_logic_vector(2 downto 0);
 
signal symbolEnable0, symbolEnable1 : std_logic;
signal symbolType0 : std_logic_vector(1 downto 0);
signal symbolContent0, symbolContent1 : std_logic_vector(31 downto 0);
signal crc5Valid : std_logic;
signal crc5 : std_logic_vector(4 downto 0);
signal crc5Calculated : std_logic_vector(4 downto 0);
 
signal crc16Valid : std_logic;
signal symbolValid : std_logic;
signal stype0Status : std_logic;
signal stype1Start : std_logic;
signal stype1End : std_logic;
signal stype1Stomp : std_logic;
signal stype1Restart : std_logic;
signal stype1LinkRequest : std_logic;
signal symbolData : std_logic;
signal crc16Data : std_logic_vector(31 downto 0);
signal crc16Current : std_logic_vector(15 downto 0);
signal crc16Temp : std_logic_vector(15 downto 0);
signal crc16Next : std_logic_vector(15 downto 0);
signal crc16Valid : std_logic;
 
signal frameContent : std_logic_vector(32*NUMBER_WORDS-1 downto 0);
 
signal rxControlWrite : std_logic;
signal rxControlSymbol : std_logic_vector(12 downto 0);
signal rxRead : std_logic;
begin
 
linkInitialized_o <= '0' when ((state = STATE_UNINITIALIZED) or
(state = STATE_PORT_INITIALIZED)) else '1';
ackIdStatus_o <= std_logic_vector(ackId);
linkInitialized_o <= operational_i;
ackIdStatus_o <= std_logic_vector(ackId_i);
inboundAckId_o <= std_logic_vector(ackId_i);
 
-----------------------------------------------------------------------------
-- Get the entries in a control symbol.
-- First pipeline stage.
-- Check the validity of the symbol, CRC5 on control symbols, and save the
-- symbol content for the next stage.
-----------------------------------------------------------------------------
 
stype0 <= rxData_i(31 downto 29);
parameter0 <= rxData_i(28 downto 24);
parameter1 <= rxData_i(23 downto 19);
stype1 <= rxData_i(18 downto 16);
cmd <= rxData_i(15 downto 13);
crc5 <= rxData_i(12 downto 8);
-- Read the fifo immediatly.
rxRead_o <= not rxEmpty_i;
 
Crc5Calculator: Crc5ITU
port map(
d_i=>rxData_i(31 downto 13), crc_o=>crc5);
 
process(clk, areset_n)
begin
if (areset_n = '0') then
crc5Valid <= '0';
symbolType0 <= (others => '0');
symbolContent0 <= (others => '0');
elsif (clk'event and clk = '1') then
if (rxEmpty_i = '0') then
if (crc5 = rxData_i(12 downto 8)) then
crc5Valid <= '1';
else
crc5Valid <= '0';
end if;
symbolEnable0 <= '1';
symbolType0 <= rxType_i;
symbolContent0 <= rxData_i;
else
symbolEnable0 <= '0';
end if;
end if;
end process;
 
-----------------------------------------------------------------------------
-- Entity for CRC-5 calculation on control symbols according to the standard.
-- Second pipeline stage.
-- Separate the part of the control symbol that are going to the transmitter
-- side and check the type of symbol for this side.
-----------------------------------------------------------------------------
 
Crc5Calculator: Crc5ITU
port map(
d_i=>rxData_i(31 downto 13), crc_o=>crc5Calculated);
process(clk, areset_n)
begin
if (areset_n = '0') then
txControlWrite_o <= '0';
txControlSymbol_o <= (others => '0');
 
symbolValid <= '0';
stype0Status <= '0';
stype1Start <= '0';
stype1End <= '0';
stype1Stomp <= '0';
stype1Restart <= '0';
stype1LinkRequest <= '0';
symbolData <= '0';
symbolContent1 <= (others => '0');
elsif (clk'event and clk = '1') then
if (symbolEnable0 = '1') then
symbolEnable1 <= '1';
symbolContent1 <= symbolContent0;
if (symbolType0 = SYMBOL_CONTROL) then
if (crc5Valid = '1') then
-- REMARK: Check if stype0 is nop and dont forward it???
symbolValid <= '1';
txControlWrite_o <= '1';
txControlSymbol_o <= symbolContent0(31 downto 19);
else
symbolValid <= '0';
txControlWrite_o <= '0';
txControlSymbol_o <= (others => '0');
end if;
else
symbolValid <= '1';
end if;
if ((symbolType0 = SYMBOL_CONTROL) and
(symbolContent0(31 downto 29) = STYPE0_STATUS)) then
stype0Status <= '1';
else
stype0Status <= '0';
end if;
if ((symbolType0 = SYMBOL_CONTROL) and
(symbolContent0(18 downto 16) = STYPE1_START_OF_PACKET)) then
stype1Start <= '1';
else
stype1Start <= '0';
end if;
if ((symbolType0 = SYMBOL_CONTROL) and
(symbolContent0(18 downto 16) = STYPE1_END_OF_PACKET)) then
stype1End <= '1';
else
stype1End <= '0';
end if;
if ((symbolType0 = SYMBOL_CONTROL) and
(symbolContent0(18 downto 16) = STYPE1_STOMP)) then
stype1Stomp <= '1';
else
stype1Stomp <= '0';
end if;
if ((symbolType0 = SYMBOL_CONTROL) and
(symbolContent0(18 downto 16) = STYPE1_RESTART_FROM_RETRY)) then
stype1Restart <= '1';
else
stype1Restart <= '0';
end if;
if ((symbolType0 = SYMBOL_CONTROL) and
(symbolContent0(18 downto 16) = STYPE1_LINK_REQUEST)) then
stype1LinkRequest <= '1';
else
stype1LinkRequest <= '0';
end if;
if (symbolType0 = SYMBOL_DATA) then
symbolData <= '1';
else
symbolData <= '0';
end if;
else
symbolEnable1 <= '0';
end if;
end if;
end process;
 
-----------------------------------------------------------------------------
-- Entities for CRC-16 calculation on 32-bit data in frames according to the
-- standard.
-- Third pipeline stage.
-- Update the CRC16 for the packet.
-- Update the buffered data and write it to the packet buffer if needed.
-- Update the main receiver state machine.
-- Generate reply symbols to the link-partner.
-- Note that this stage cannot contain any registers as it could be cascaded
-- to other cores.
-----------------------------------------------------------------------------
-----------------------------------------------------------------------------
-- CRC-calculation.
-- Add a data symbol to the calculated CRC for the packet.
-- controlSymbol->just forward old crc16.
-- first data-symbol in packet->crc_o is product of 11111 and the
-- symbolContent1 without ackid.
-- not first data-symbol->crc_o is product of crc_i and symbolContent1.
-----------------------------------------------------------------------------
 
-- If the CRC is correct, there is either zero in crc16Next if no pad exists
-- or zero in crc16Temp and crc16Data(15 downto 0). This means that crc16Next
-- will always be zero here if the CRC is correct.
crc16Valid <= '1' when (crc16Next = x"0000") else '0';
crc16Data(31 downto 26) <= "000000" when (unsigned(frameIndex_i) = 1) else
symbolContent1(31 downto 26);
crc16Data(25 downto 0) <= symbolContent1(25 downto 0);
 
Crc16High: Crc16CITT
crc16Current <= crc_i when (unsigned(frameIndex_i) /= 1) else
(others => '1');
 
Crc16Msb: Crc16CITT
port map(
d_i=>crc16Data(31 downto 16), crc_i=>crc16Current, crc_o=>crc16Temp);
Crc16Low: Crc16CITT
Crc16Lsb: Crc16CITT
port map(
d_i=>crc16Data(15 downto 0), crc_i=>crc16Temp, crc_o=>crc16Next);
 
crc_o <= crc_i when (symbolData = '0') else
crc16Next;
 
crc16Valid <= '1' when (crc_i = x"0000") else '0';
 
-----------------------------------------------------------------------------
-- Main inbound symbol handler.
-- Update buffered data.
-----------------------------------------------------------------------------
rxRead_o <= rxRead;
inboundAckId_o <= std_logic_vector(ackId);
process(areset_n, clk)
begin
if (areset_n = '0') then
state <= STATE_UNINITIALIZED;
rxRead <= '0';
txControlWrite_o <= '0';
txControlSymbol_o <= (others => '0');
rxControlWrite_o <= '0';
rxControlSymbol_o <= (others => '0');
 
writeFrame_o <= '0';
writeFrameAbort_o <= '0';
writeContent_o <= '0';
writeContentData_o <= (others => '0');
-- Append the new symbol content to the end of the
-- current frame content if the symbol is a data symbol.
frameContentSingle:
if (NUMBER_WORDS = 1) generate
frameContent <= symbolContent1;
end generate;
frameContentMulti:
if (NUMBER_WORDS > 1) generate
frameContent <=
(frameContent_i((32*(NUMBER_WORDS-1))-1 downto 0) & symbolContent1) when (symbolData = '1') else
frameContent_i;
end generate;
 
-- REMARK: Use frameIndex instead of this...
statusCounter <= 0;
-- Update outputs.
enable_o <= symbolEnable1;
frameContent_o <= frameContent;
writeContentData_o <= frameContent;
frameIndex <= 0;
ackId <= (others => '0');
-----------------------------------------------------------------------------
-- Main inbound symbol handler.
-----------------------------------------------------------------------------
process(portInitialized_i, portEnable_i, writeFrameFull_i,
operational_i, ackId_i, frameIndex_i, frameWordCounter_i,
inputRetryStopped_i, inputErrorStopped_i,
symbolValid,
stype0Status,
stype1Start, stype1End, stype1Stomp, stype1Restart, stype1LinkRequest,
symbolData,
symbolContent1,
frameContent,
crc16Valid)
begin
operational_o <= operational_i;
ackId_o <= ackId_i;
frameIndex_o <= frameIndex_i;
frameWordCounter_o <= frameWordCounter_i;
inputRetryStopped_o <= inputRetryStopped_i;
inputErrorStopped_o <= inputErrorStopped_i;
rxControlWrite <= '0';
rxControlSymbol <= (others => '0');
writeFrame_o <= '0';
writeFrameAbort_o <= '0';
writeContent_o <= '0';
writeContentWords_o <= (others => '0');
 
crc16Current <= (others => '0');
crc16Data <= (others => '0');
elsif (clk'event and clk = '1') then
rxRead <= '0';
txControlWrite_o <= '0';
rxControlWrite_o <= '0';
writeFrame_o <= '0';
writeFrameAbort_o <= '0';
writeContent_o <= '0';
 
-- Check if a locakAckIdWrite is active.
if (localAckIdWrite_i = '1') then
-- A localAckIdWrite is active.
-- Set ackId.
ackId <= unsigned(inboundAckId_i);
else
-- A localAckIdWrite is not active.
 
-- Act on the current state.
case state is
-- Act on the current state.
if (operational_i = '0') then
---------------------------------------------------------------------
-- The port is not operational and is waiting for status control
-- symbols to be received on the link. Count the number
-- of error-free status symbols and considder the link operational
-- when enough of them has been received. Frames are not allowed
-- here.
---------------------------------------------------------------------
-- Check if the port is initialized.
if (portInitialized_i = '1') then
-- Port is initialized.
-- Check if the control symbol has a valid checksum.
if (symbolValid = '1') then
-- The control symbol has a valid checksum.
when STATE_UNINITIALIZED =>
-----------------------------------------------------------------------
-- This state is entered at startup. A port that is not initialized
-- should discard all received symbols.
-----------------------------------------------------------------------
-- Check the stype0 part if we should count the number of
-- error-free status symbols.
if (stype0Status = '1') then
-- The symbol is a status.
-- Check if the port is initialized.
if (portInitialized_i = '0') then
-- Port not initialized.
-- Check if enough status symbols have been received.
if (unsigned(frameIndex_i) = 7) then
-- Enough status symbols have been received.
 
-- Check if a new symbol is ready to be read.
if (rxRead = '0') and (rxEmpty_i = '0') then
-- New symbol ready.
-- Discard all received symbols in this state.
rxRead <= '1';
else
-- No new symbol ready to be read.
-- Dont do anything.
end if;
-- Reset all packets.
frameIndex_o <= (others => '0');
writeFrameAbort_o <= '1';
 
-- Set the link as initialized.
operational_o <= '1';
else
-- Port is initialized.
-- Go to the initialized state and reset the counters.
state <= STATE_PORT_INITIALIZED;
statusCounter <= 0;
-- Increase the number of error-free status symbols that
-- has been received.
frameIndex_o <= std_logic_vector(unsigned(frameIndex_i) + 1);
end if;
else
-- The symbol is not a status.
-- Dont do anything.
end if;
else
-- A control symbol with CRC5 error was recevied.
frameIndex_o <= (others => '0');
end if;
else
-- The port has become uninitialized.
frameIndex_o <= (others => '0');
end if;
else
---------------------------------------------------------------------
-- The port has been initialized and enough error free status symbols
-- have been received. Forward data frames to the frame buffer
-- interface. This is the normal operational state.
---------------------------------------------------------------------
-- Check that the port is initialized.
if (portInitialized_i = '1') then
-- The port and link is initialized.
-- Check if the control symbol has a valid CRC-5.
if (symbolValid = '1') then
-- The symbol is correct.
 
when STATE_PORT_INITIALIZED =>
---------------------------------------------------------------------
-- The port has been initialized and status control symbols are being
-- received on the link to check if it is working. Count the number
-- of error-free status symbols and considder the link initialized
-- when enough of them has been received. Frames are not allowed
-- here.
---------------------------------------------------------------------
if ((stype1Start = '1') and
(inputRetryStopped_i = '0') and (inputErrorStopped_i = '0')) then
-------------------------------------------------------------
-- Start the reception of a new frame or end a currently
-- ongoing frame and start a new one.
-------------------------------------------------------------
-- Check if the port is initialized.
if (portInitialized_i = '1') then
-- Port is initialized.
-- Check if a frame has already been started.
if (unsigned(frameIndex_i) /= 0) then
-- A frame is already started.
-- Complete the last frame and start to ackumulate a new one
-- and update the ackId.
-- Check if a new symbol is ready to be read.
if (rxRead = '0') and (rxEmpty_i = '0') then
-- There is a new symbol to read.
if (unsigned(frameIndex_i) > 3) then
 
-- Check the type of symbol.
if (rxControl_i = SYMBOL_CONTROL) then
-- This is a control symbol that is not a packet delimiter.
-- Reset the frame index to indicate the frame is started.
frameIndex_o <= "0000001";
frameWordCounter_o <= (others=>'0');
-- Check the CRC-16 and the length of the received frame.
if (crc16Valid = '1') then
-- The CRC-16 is ok.
 
-- Check if there are any unwritten buffered packet content
-- and write it if there is.
-- REMARK: Multi-symbol support...
if (unsigned(frameWordCounter_i) /= 0) then
writeContent_o <= '1';
end if;
-- Check if the control symbol has a valid checksum.
if (crc5Calculated = crc5) then
-- The control symbol has a valid checksum.
-- Update the frame buffer to indicate that the frame has
-- been completly received.
writeFrame_o <= '1';
 
-- Forward the stype0 part of the symbol to the transmitter.
txControlWrite_o <= '1';
txControlSymbol_o <= stype0 & parameter0 & parameter1;
-- Check the stype0 part if we should count the number of
-- error-free status symbols.
if (stype0 = STYPE0_STATUS) then
-- The symbol is a status.
-- Update ackId.
ackId_o <= ackId_i + 1;
 
-- Check if enough status symbols have been received.
if (statusCounter = 7) then
-- Enough status symbols have been received.
-- Send packet-accepted.
-- The buffer status is appended by the transmitter
-- when sent to get the latest number.
rxControlWrite <= '1';
rxControlSymbol <= STYPE0_PACKET_ACCEPTED &
std_logic_vector(ackId_i) &
"11111";
else
-- The CRC-16 is not ok.
 
-- Reset all packets.
frameIndex <= 0;
writeFrameAbort_o <= '1';
 
-- Set the link as initialized.
state <= STATE_NORMAL;
else
-- Increase the number of error-free status symbols that
-- has been received.
statusCounter <= statusCounter + 1;
end if;
else
-- The symbol is not a status.
-- Dont do anything.
end if;
else
-- A control symbol with CRC5 error was recevied.
statusCounter <= 0;
end if;
else
-- Symbol that is not allowed in this state have been received.
-- Discard it.
-- Make the transmitter send a packet-not-accepted to indicate
-- that the received packet contained a CRC error.
rxControlWrite <= '1';
rxControlSymbol <= STYPE0_PACKET_NOT_ACCEPTED &
"00000" &
PACKET_NOT_ACCEPTED_CAUSE_PACKET_CRC;
inputErrorStopped_o <= '1';
end if;
-- Update to the next symbol.
rxRead <= '1';
else
-- No new symbol ready to be read.
-- Dont do anything.
-- This packet is too small.
-- Make the transmitter send a packet-not-accepted to indicated
-- that the received packet was too small.
rxControlWrite <= '1';
rxControlSymbol <= STYPE0_PACKET_NOT_ACCEPTED &
"00000" &
PACKET_NOT_ACCEPTED_CAUSE_GENERAL_ERROR;
inputErrorStopped_o <= '1';
end if;
else
-- Go back to the uninitialized state.
state <= STATE_UNINITIALIZED;
-- No frame has been started.
-- Reset the frame index to indicate the frame is started.
frameIndex_o <= "0000001";
frameWordCounter_o <= (others=>'0');
end if;
 
when STATE_NORMAL =>
---------------------------------------------------------------------
-- The port has been initialized and enough error free status symbols
-- have been received. Forward data frames to the frame buffer
-- interface. This is the normal operational state.
---------------------------------------------------------------------
end if;
if ((stype1End = '1') and
(inputRetryStopped_i = '0') and (inputErrorStopped_i = '0')) then
-------------------------------------------------------------
-- End the reception of an old frame.
-------------------------------------------------------------
-- Check that the port is initialized.
if (portInitialized_i = '1') then
-- The port and link is initialized.
-- Check if a frame has already been started.
if (unsigned(frameIndex_i) > 3) then
-- A frame has been started and it is large enough.
-- Check if a new symbol is ready to be read.
if (rxRead = '0') and (rxEmpty_i = '0') then
-- There is a new symbol to read.
-- Reset frame reception to indicate that no frame is ongoing.
frameIndex_o <= (others => '0');
-- Check the CRC-16 and the length of the received frame.
if (crc16Valid = '1') then
-- The CRC-16 is ok.
 
-- Check the type of symbol.
if (rxControl_i = SYMBOL_CONTROL) then
-- This is a control symbol with or without a packet delimiter.
-- Check if the control symbol has a valid CRC-5.
if (crc5Calculated = crc5) then
-- The control symbol is correct.
 
-- Forward the stype0 part of the symbol to the transmitter.
txControlWrite_o <= '1';
txControlSymbol_o <= stype0 & parameter0 & parameter1;
-- Check if there are any unwritten buffered packet content
-- and write it if there is.
-- REMARK: Multi-symbol support...
if (unsigned(frameWordCounter_i) /= 0) then
writeContent_o <= '1';
end if;
-- Check the stype1 part.
case stype1 is
when STYPE1_START_OF_PACKET =>
-------------------------------------------------------------
-- Start the reception of a new frame or end a currently
-- ongoing frame.
-------------------------------------------------------------
-- Check if a frame has already been started.
if (frameIndex /= 0) then
-- A frame is already started.
-- Complete the last frame and start to ackumulate a new one
-- and update the ackId.
-- Update the frame buffer to indicate that the frame has
-- been completly received.
writeFrame_o <= '1';
 
-- Check the CRC-16 and the length of the received frame.
if (crc16Valid = '1') and (frameIndex > 3) then
-- The CRC-16 is ok.
-- Update ackId.
ackId_o <= ackId_i + 1;
 
-- Reset the frame index to indicate the frame is started.
frameIndex <= 1;
-- Update the frame buffer to indicate that the frame has
-- been completly received.
writeFrame_o <= '1';
-- Send packet-accepted.
-- The buffer status is appended by the transmitter
-- when sent to get the latest number.
rxControlWrite <= '1';
rxControlSymbol <= STYPE0_PACKET_ACCEPTED &
std_logic_vector(ackId_i) &
"11111";
else
-- The CRC-16 is not ok.
 
-- Update ackId.
ackId <= ackId + 1;
 
-- Send packet-accepted.
-- The buffer status is appended by the transmitter
-- when sent to get the latest number.
rxControlWrite_o <= '1';
rxControlSymbol_o <= STYPE0_PACKET_ACCEPTED & std_logic_vector(ackId) & "11111";
else
-- The CRC-16 is not ok.
 
-- Make the transmitter send a packet-not-accepted to indicate
-- that the received packet contained a CRC error.
rxControlWrite_o <= '1';
rxControlSymbol_o <= STYPE0_PACKET_NOT_ACCEPTED &
"00000" &
PACKET_NOT_ACCEPTED_CAUSE_PACKET_CRC;
state <= STATE_INPUT_ERROR_STOPPED;
end if;
else
-- No frame has been started.
 
-- Reset the frame index to indicate the frame is started.
frameIndex <= 1;
end if;
when STYPE1_END_OF_PACKET =>
-------------------------------------------------------------
-- End the reception of an old frame.
-------------------------------------------------------------
 
-- Check the CRC-16 and the length of the received frame.
if (crc16Valid = '1') and (frameIndex > 3) then
-- The CRC-16 is ok.
-- Reset frame reception to indicate that no frame is ongoing.
frameIndex <= 0;
-- Update the frame buffer to indicate that the frame has
-- been completly received.
writeFrame_o <= '1';
 
-- Update ackId.
ackId <= ackId + 1;
 
-- Send packet-accepted.
-- The buffer status is appended by the transmitter
-- when sent to get the latest number.
rxControlWrite_o <= '1';
rxControlSymbol_o <= STYPE0_PACKET_ACCEPTED & std_logic_vector(ackId) & "11111";
else
-- The CRC-16 is not ok.
 
-- Make the transmitter send a packet-not-accepted to indicate
-- that the received packet contained a CRC error.
rxControlWrite_o <= '1';
rxControlSymbol_o <= STYPE0_PACKET_NOT_ACCEPTED &
"00000" &
PACKET_NOT_ACCEPTED_CAUSE_PACKET_CRC;
state <= STATE_INPUT_ERROR_STOPPED;
end if;
when STYPE1_STOMP =>
-------------------------------------------------------------
-- Restart the reception of an old frame.
-------------------------------------------------------------
-- See 5.10 in the standard.
-- Make the transmitter send a packet-retry to indicate
-- that the packet cannot be accepted.
rxControlWrite_o <= '1';
rxControlSymbol_o <= STYPE0_PACKET_RETRY & std_logic_vector(ackId) & "11111";
 
-- Enter the input retry-stopped state.
state <= STATE_INPUT_RETRY_STOPPED;
when STYPE1_RESTART_FROM_RETRY =>
-------------------------------------------------------------
-- The receiver indicates a restart from a retry sent
-- from us.
-------------------------------------------------------------
-- See 5.10 in the standard.
-- Protocol error, this symbol should not be received here since
-- we should have been in input-retry-stopped.
-- Send a packet-not-accepted to indicate that a protocol
-- error has occurred.
rxControlWrite_o <= '1';
rxControlSymbol_o <= STYPE0_PACKET_NOT_ACCEPTED &
"00000" &
PACKET_NOT_ACCEPTED_CAUSE_GENERAL_ERROR;
state <= STATE_INPUT_ERROR_STOPPED;
when STYPE1_LINK_REQUEST =>
-------------------------------------------------------------
-- Reply to a LINK-REQUEST.
-------------------------------------------------------------
 
-- Check the command part.
if (cmd = "100") then
-- Return input port status command.
-- This functions as a link-request(restart-from-error)
-- control symbol under error situations.
-- Send a link response containing an ok reply.
rxControlWrite_o <= '1';
rxControlSymbol_o <= STYPE0_LINK_RESPONSE & std_logic_vector(ackId) & "10000";
elsif (cmd = "011") then
-- Reset device command.
-- Discard this.
else
-- Unsupported command.
-- Discard this.
end if;
-- Abort the frame and reset frame reception.
frameIndex <= 0;
writeFrameAbort_o <= '1';
when STYPE1_MULTICAST_EVENT =>
-------------------------------------------------------------
-- Multicast symbol.
-------------------------------------------------------------
-- Discard the symbol.
when STYPE1_RESERVED =>
-------------------------------------------------------------
-- Reserved.
-------------------------------------------------------------
-- Not supported, dont do anything.
when STYPE1_NOP =>
-------------------------------------------------------------
-- NOP, no operation.
-------------------------------------------------------------
-- Dont do anything.
 
when others =>
-------------------------------------------------------------
--
-------------------------------------------------------------
-- NOP, no operation, dont do anything.
null;
end case;
else
-- The control symbol contains a crc error.
 
-- Send a packet-not-accepted to indicate that a corrupted
-- control-symbol has been received and change state.
rxControlWrite_o <= '1';
rxControlSymbol_o <= STYPE0_PACKET_NOT_ACCEPTED &
"00000" &
PACKET_NOT_ACCEPTED_CAUSE_CONTROL_CRC;
state <= STATE_INPUT_ERROR_STOPPED;
end if;
elsif (rxControl_i = SYMBOL_DATA) then
-- This is a data symbol.
-- REMARK: Add check for in-the-middle-crc here...
-- Check if a frame has been started.
-- Index=0 not started
-- index=1 started and expecting to receive the first data.
-- index=others, the index of the received data.
if (frameIndex /= 0) and (frameIndex /= 70) then
-- A frame has been started and is not too long.
 
-- Check if the ackId is correct.
if (((frameIndex = 1) and (unsigned(rxData_i(31 downto 27)) = ackId)) or
(frameIndex /= 1)) then
-- This is the first data symbol containing the ackId which
-- is matching or receiving the rest of the frame.
 
-- Check if the packet ftype is allowed.
-- If the portEnable is deasserted only maintenance
-- packets are allowed.
if (((frameIndex = 1) and
((portEnable_i = '1') or (rxData_i(19 downto 16) = FTYPE_MAINTENANCE_CLASS))) or
(frameIndex /= 1)) then
-- The packet is allowed.
 
-- Check if there is buffers available to store the new packet.
if(writeFrameFull_i = '0') then
-- There is buffering space available to store the new data.
-- Write the data to the frame FIFO.
writeContent_o <= '1';
writeContentData_o <= rxData_i;
 
-- Increment the number of received data symbols.
frameIndex <= frameIndex + 1;
-- Update the saved crc result with the output from the CRC calculation.
if (frameIndex = 1) then
-- Note that the ackId should not be included when the CRC
-- is calculated.
crc16Data <= "000000" & rxData_i(25 downto 0);
crc16Current <= (others => '1');
else
crc16Data <= rxData_i;
crc16Current <= crc16Next;
end if;
else
-- The packet buffer is full.
-- Let the link-partner resend the packet.
rxControlWrite_o <= '1';
rxControlSymbol_o <= STYPE0_PACKET_RETRY & std_logic_vector(ackId) & "11111";
state <= STATE_INPUT_RETRY_STOPPED;
end if;
else
-- The non-maintenance packets are not allowed.
-- Send packet-not-accepted.
rxControlWrite_o <= '1';
rxControlSymbol_o <=
STYPE0_PACKET_NOT_ACCEPTED & "00000" & PACKET_NOT_ACCEPTED_CAUSE_NON_MAINTENANCE_STOPPED;
state <= STATE_INPUT_ERROR_STOPPED;
end if;
else
-- The ackId is unexpected.
-- Send packet-not-accepted.
rxControlWrite_o <= '1';
rxControlSymbol_o <=
STYPE0_PACKET_NOT_ACCEPTED & "00000" & PACKET_NOT_ACCEPTED_CAUSE_UNEXPECTED_ACKID;
state <= STATE_INPUT_ERROR_STOPPED;
end if;
else
-- A frame has not been started or is too long.
-- Send packet-not-accepted.
rxControlWrite_o <= '1';
rxControlSymbol_o <= STYPE0_PACKET_NOT_ACCEPTED & "00000" & PACKET_NOT_ACCEPTED_CAUSE_GENERAL_ERROR;
state <= STATE_INPUT_ERROR_STOPPED;
end if;
else
-- Idle sequence received.
-- Discard these.
end if;
 
-- Update to the next symbol.
rxRead <= '1';
else
-- No new symbol received.
-- Dont do anything.
-- Make the transmitter send a packet-not-accepted to indicate
-- that the received packet contained a CRC error.
rxControlWrite <= '1';
rxControlSymbol <= STYPE0_PACKET_NOT_ACCEPTED &
"00000" &
PACKET_NOT_ACCEPTED_CAUSE_PACKET_CRC;
inputErrorStopped_o <= '1';
end if;
else
-- The port has become uninitialized.
-- Go back to the uninitialized state.
state <= STATE_UNINITIALIZED;
-- This packet is too small.
-- Make the transmitter send a packet-not-accepted to indicate
-- that the received packet was too small.
rxControlWrite <= '1';
rxControlSymbol <= STYPE0_PACKET_NOT_ACCEPTED &
"00000" &
PACKET_NOT_ACCEPTED_CAUSE_GENERAL_ERROR;
inputErrorStopped_o <= '1';
end if;
end if;
 
when STATE_INPUT_RETRY_STOPPED =>
---------------------------------------------------------------------
-- This state is entered when a frame could not be accepted. All
-- symbols except restart-from-retry and link-request are discarded.
-- A restart-from-retry triggers a state change into the normal
-- link-initialized state.
---------------------------------------------------------------------
if ((stype1Stomp = '1') and
(inputRetryStopped_i = '0') and (inputErrorStopped_i = '0')) then
-------------------------------------------------------------
-- Restart the reception of an old frame.
-------------------------------------------------------------
-- See 5.10 in the standard.
-- Check that the port is initialized.
if (portInitialized_i = '1') then
-- The port and link is initialized.
-- Check if a new symbol is ready to be read.
if (rxRead = '0') and (rxEmpty_i = '0') then
-- There is a new symbol to read.
-- Make the transmitter send a packet-retry to indicate
-- that the packet cannot be accepted.
rxControlWrite <= '1';
rxControlSymbol <= STYPE0_PACKET_RETRY &
std_logic_vector(ackId_i) &
"11111";
-- Enter the input retry-stopped state.
inputRetryStopped_o <= '1';
end if;
 
-- Check the type of symbol.
if (rxControl_i = SYMBOL_CONTROL) then
-- This is a control symbol with or without a packet delimiter.
-- Check if the control symbol has a valid CRC-5.
if (crc5Calculated = crc5) then
-- The control symbol is correct.
if (stype1Restart = '1') then
if (inputRetryStopped_i = '1') then
-------------------------------------------------------------
-- The receiver indicates a restart from a retry sent
-- from us.
-------------------------------------------------------------
 
-- Forward the stype0 part of the symbol to the transmitter.
txControlWrite_o <= '1';
txControlSymbol_o <= stype0 & parameter0 & parameter1;
-- Check the stype1 part.
case stype1 is
when STYPE1_RESTART_FROM_RETRY =>
-------------------------------------------------------------
-- The receiver indicates a restart from a retry sent
-- from us.
-------------------------------------------------------------
-- Abort the frame and reset frame reception.
frameIndex_o <= (others => '0');
writeFrameAbort_o <= '1';
-- Go back to the normal operational state.
inputRetryStopped_o <= '0';
else
-------------------------------------------------------------
-- The receiver indicates a restart from a retry sent
-- from us.
-------------------------------------------------------------
-- See 5.10 in the standard.
-- Protocol error, this symbol should not be received here since
-- we should have been in input-retry-stopped.
-- Send a packet-not-accepted to indicate that a protocol
-- error has occurred.
rxControlWrite <= '1';
rxControlSymbol <= STYPE0_PACKET_NOT_ACCEPTED &
"00000" &
PACKET_NOT_ACCEPTED_CAUSE_GENERAL_ERROR;
inputErrorStopped_o <= '1';
end if;
end if;
 
-- Abort the frame and reset frame reception.
frameIndex <= 0;
writeFrameAbort_o <= '1';
-- Go back to the normal operational state.
state <= STATE_NORMAL;
when STYPE1_LINK_REQUEST =>
-------------------------------------------------------------
-- Received a link-request.
-------------------------------------------------------------
if (stype1LinkRequest = '1') then
-------------------------------------------------------------
-- Reply to a LINK-REQUEST.
-------------------------------------------------------------
-- Check the command part.
if (symbolContent1(15 downto 13) = "100") then
-- Return input port status command.
-- This functions as a link-request(restart-from-error)
-- control symbol under error situations.
 
-- Check the command part.
if (cmd = "100") then
-- Return input port status command.
-- This functions as a link-request(restart-from-error)
-- control symbol under error situations.
-- Send a link response containing an ok reply.
rxControlWrite_o <= '1';
rxControlSymbol_o <= STYPE0_LINK_RESPONSE & std_logic_vector(ackId) & "00100";
elsif (cmd = "011") then
-- Reset device command.
-- Discard this.
else
-- Unsupported command.
-- Discard this.
end if;
-- Abort the frame and reset frame reception.
frameIndex <= 0;
writeFrameAbort_o <= '1';
-- Go back to the normal operational state.
state <= STATE_NORMAL;
when others =>
-------------------------------------------------------------
--
-------------------------------------------------------------
-- Discard other control symbols.
null;
end case;
else
-- The control symbol contains a crc error.
 
-- Send a packet-not-accepted to indicate that a corrupted
-- control-symbol has been received and change state.
rxControlWrite_o <= '1';
rxControlSymbol_o <= STYPE0_PACKET_NOT_ACCEPTED &
"00000" &
PACKET_NOT_ACCEPTED_CAUSE_CONTROL_CRC;
state <= STATE_INPUT_ERROR_STOPPED;
end if;
elsif (rxControl_i = SYMBOL_DATA) then
-- This is a data symbol.
-- Discard all data symbols in this state.
else
-- Idle sequence received.
-- Discard other symbols.
end if;
 
-- Update to the next symbol.
rxRead <= '1';
if (inputErrorStopped_i = '1') then
rxControlWrite <= '1';
rxControlSymbol <= STYPE0_LINK_RESPONSE &
std_logic_vector(ackId_i) &
"00101";
elsif (inputRetryStopped_i = '1') then
rxControlWrite <= '1';
rxControlSymbol <= STYPE0_LINK_RESPONSE &
std_logic_vector(ackId_i) &
"00100";
else
-- No new symbol received.
-- Dont do anything.
-- Send a link response containing an ok reply.
rxControlWrite <= '1';
rxControlSymbol <= STYPE0_LINK_RESPONSE &
std_logic_vector(ackId_i) &
"10000";
end if;
else
-- The port has become uninitialized.
-- Go back to the uninitialized state.
state <= STATE_UNINITIALIZED;
-- Reset device command or other unsupported command.
-- Discard this.
end if;
when STATE_INPUT_ERROR_STOPPED =>
---------------------------------------------------------------------
-- This state is entered when an error situation has occurred. When in this
-- state, all symbols should be discarded until a link-request-symbols has
-- been received. See section 5.13.2.6 in part 6 of the standard.
-- Note that it is only the input side of the port that are affected, not the
-- output side. Packets may still be transmitted and acknowledges should be
-- accepted.
---------------------------------------------------------------------
-- Check that the port is initialized.
if (portInitialized_i = '1') then
-- The port and link is initialized.
-- Check if a new symbol is ready to be read.
if (rxRead = '0') and (rxEmpty_i = '0') then
-- There is a new symbol to read.
-- Abort the frame and reset frame reception.
inputRetryStopped_o <= '0';
inputErrorStopped_o <= '0';
frameIndex_o <= (others=>'0');
writeFrameAbort_o <= '1';
end if;
 
-- Check the type of symbol.
if (rxControl_i = SYMBOL_CONTROL) then
-- This is a control symbol with or without a packet delimiter.
-- Check if the control symbol has a valid CRC-5.
if (crc5Calculated = crc5) then
-- The control symbol is correct.
if ((symbolData = '1') and
(inputRetryStopped_i = '0') and (inputErrorStopped_i = '0')) then
-------------------------------------------------------------
-- This is a data symbol.
-------------------------------------------------------------
-- REMARK: Add check for in-the-middle-crc here...
 
-- Forward the stype0 part of the symbol to the transmitter.
txControlWrite_o <= '1';
txControlSymbol_o <= stype0 & parameter0 & parameter1;
-- Check the stype1 part.
case stype1 is
case frameIndex_i is
when "0000000" | "1000110" =>
-- A frame has not been started or is too long.
-- Send packet-not-accepted.
rxControlWrite <= '1';
rxControlSymbol <= STYPE0_PACKET_NOT_ACCEPTED &
"00000" &
PACKET_NOT_ACCEPTED_CAUSE_GENERAL_ERROR;
inputErrorStopped_o <= '1';
when "0000001" =>
if (unsigned(symbolContent1(31 downto 27)) = ackId_i) then
if ((portEnable_i = '1') or
(symbolContent1(19 downto 16) = FTYPE_MAINTENANCE_CLASS)) then
 
-- Check if there are buffers available to store the new
-- packet.
if (writeFrameFull_i = '0') then
-- There are buffering space available to store the new
-- data.
-- Check if the buffer entry is ready to be written
-- into the packet buffer.
-- REMARK: Multi-symbol support...
if (unsigned(frameWordCounter_i) = (NUMBER_WORDS-1)) then
-- Write the data to the frame FIFO.
frameWordCounter_o <= (others=>'0');
writeContent_o <= '1';
writeContentWords_o <= frameWordCounter_i;
else
frameWordCounter_o <= std_logic_vector(unsigned(frameWordCounter_i) + 1);
end if;
when STYPE1_LINK_REQUEST =>
-------------------------------------------------------------
-- Received a link-request.
-------------------------------------------------------------
 
-- Check the command part.
-- REMARK: Should also send a status-control-symbol
-- directly following this symbol...
if (cmd = "100") then
-- Return input port status command.
-- This functions as a link-request(restart-from-error)
-- control symbol under error situations.
-- Send a link response containing an ok reply.
rxControlWrite_o <= '1';
rxControlSymbol_o <= STYPE0_LINK_RESPONSE & std_logic_vector(ackId) & "00101";
elsif (cmd = "011") then
-- Reset device command.
-- Discard this.
else
-- Unsupported command.
-- Discard this.
end if;
-- Abort the frame and reset frame reception.
frameIndex <= 0;
writeFrameAbort_o <= '1';
-- Go back to the normal operational state.
state <= STATE_NORMAL;
when others =>
-------------------------------------------------------------
--
-------------------------------------------------------------
-- Discard other control symbols.
null;
end case;
-- Increment the number of received data symbols.
frameIndex_o <= std_logic_vector(unsigned(frameIndex_i) + 1);
else
-- The packet buffer is full.
-- Let the link-partner resend the packet.
rxControlWrite <= '1';
rxControlSymbol <= STYPE0_PACKET_RETRY &
std_logic_vector(ackId_i) &
"11111";
inputRetryStopped_o <= '1';
end if;
else
-- The control symbol contains a crc error.
-- Error is ignored in this state.
-- A non-maintenance packets are not allowed.
-- Send packet-not-accepted.
rxControlWrite <= '1';
rxControlSymbol <= STYPE0_PACKET_NOT_ACCEPTED &
"00000" &
PACKET_NOT_ACCEPTED_CAUSE_NON_MAINTENANCE_STOPPED;
inputErrorStopped_o <= '1';
end if;
else
-- Other symbol received.
-- All other symbols are discarded in this state.
-- The ackId is unexpected.
-- Send packet-not-accepted.
rxControlWrite <= '1';
rxControlSymbol <= STYPE0_PACKET_NOT_ACCEPTED &
"00000" &
PACKET_NOT_ACCEPTED_CAUSE_UNEXPECTED_ACKID;
inputErrorStopped_o <= '1';
end if;
when others =>
-- A frame has been started and is not too long.
-- Check if the buffer entry is ready to be written
-- into the packet buffer.
-- REMARK: Multi-symbol support...
if (unsigned(frameWordCounter_i) = (NUMBER_WORDS-1)) then
-- Write the data to the frame FIFO.
frameWordCounter_o <= (others=>'0');
writeContent_o <= '1';
writeContentWords_o <= frameWordCounter_i;
else
frameWordCounter_o <= std_logic_vector(unsigned(frameWordCounter_i) + 1);
end if;
 
-- Update to the next symbol.
rxRead <= '1';
else
-- No new symbol received.
-- Dont do anything.
end if;
else
-- The port has become uninitialized.
-- Go back to the uninitialized state.
state <= STATE_UNINITIALIZED;
end if;
-- Increment the number of received data symbols.
frameIndex_o <= std_logic_vector(unsigned(frameIndex_i) + 1);
end case;
end if;
else
-- A control symbol contains a crc error.
 
when others =>
---------------------------------------------------------------------
--
---------------------------------------------------------------------
null;
end case;
-- Send a packet-not-accepted to indicate that a corrupted
-- control-symbol has been received and change state.
rxControlWrite <= '1';
rxControlSymbol <= STYPE0_PACKET_NOT_ACCEPTED &
"00000" &
PACKET_NOT_ACCEPTED_CAUSE_CONTROL_CRC;
inputErrorStopped_o <= '1';
end if;
else
-- The port has become uninitialized.
-- Go back to the uninitialized state.
operational_o <= '0';
end if;
end if;
end process;
 
-----------------------------------------------------------------------------
-- Fourth pipeline stage.
-----------------------------------------------------------------------------
-- REMARK: Do more stuff in this stage, convert a one-hot to the symbol to
-- send...
-- REMARK: Register other outputs here like writeContent_o...
 
process(clk, areset_n)
begin
if (areset_n = '0') then
rxControlWrite_o <= '0';
rxControlSymbol_o <= (others=>'0');
elsif (clk'event and clk = '1') then
rxControlWrite_o <= rxControlWrite and symbolEnable1;
rxControlSymbol_o <= rxControlSymbol;
end if;
end process;
end architecture;
 
 
2490,3 → 2813,85
crc_o(4) <= c(0); crc_o(3) <= c(1); crc_o(2) <= c(2); crc_o(1) <= c(3);
crc_o(0) <= c(4);
end architecture;
 
 
-------------------------------------------------------------------------------
--
-------------------------------------------------------------------------------
library ieee;
use ieee.std_logic_1164.all;
use ieee.numeric_std.all;
use work.rio_common.all;
 
-------------------------------------------------------------------------------
--
-------------------------------------------------------------------------------
entity Crc16Calculator is
generic (
NUMBER_WORDS : natural range 1 to 8 := 1);
 
port (
clk : in std_logic;
areset_n : in std_logic;
write_i : in std_logic;
crc_i : in std_logic_vector(15 downto 0);
data_i : in std_logic_vector((32*NUMBER_WORDS)-1 downto 0);
 
crc_o : out std_logic_vector(15 downto 0);
done_o : out std_logic);
 
end Crc16Calculator;
 
-------------------------------------------------------------------------------
--
-------------------------------------------------------------------------------
architecture Crc16CalculatorImpl of Crc16Calculator is
 
component Crc16CITT is
port(
d_i : in std_logic_vector(15 downto 0);
crc_i : in std_logic_vector(15 downto 0);
crc_o : out std_logic_vector(15 downto 0));
end component;
 
signal iterator : natural range 0 to 2*NUMBER_WORDS;
signal crcData : std_logic_vector((32*NUMBER_WORDS)-1 downto 0);
signal crcCurrent : std_logic_vector(15 downto 0);
signal crcNext : std_logic_vector(15 downto 0);
begin
 
process(areset_n, clk)
begin
if (areset_n = '0') then
iterator <= 0;
done_o <= '0';
crc_o <= (others => '0');
elsif (clk'event and clk = '1') then
if (write_i = '1') then
iterator <= 2*NUMBER_WORDS-1;
crcData <= data_i;
crcCurrent <= crc_i;
done_o <= '0';
else
if (iterator /= 0) then
iterator <= iterator - 1;
crcData <= crcData(((32*NUMBER_WORDS)-1)-16 downto 0) & x"0000";
crcCurrent <= crcNext;
else
crc_o <= crcNext;
done_o <= '1';
end if;
end if;
end if;
end process;
Crc16Inst: Crc16CITT
port map(
d_i=>crcData((32*NUMBER_WORDS)-1 downto (32*NUMBER_WORDS)-16),
crc_i=>crcCurrent, crc_o=>crcNext);
end architecture;

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