URL
https://opencores.org/ocsvn/hdlc/hdlc/trunk
Subversion Repositories hdlc
[/] [hdlc/] [trunk/] [CODE/] [SPMEM.VHD] - Rev 17
Compare with Previous | Blame | View Log
--------------------------------------------------------------------------------- Title : Single port RAM-- Project : Memory Cores--------------------------------------------------------------------------------- File : spmem.vhd-- Author : Jamil Khatib (khatib@ieee.org)-- Organization: OpenIPCore Project-- Created : 1999/5/14-- Last update : 2000/12/19-- Platform :-- Simulators : Modelsim 5.3XE/Windows98-- Synthesizers: Leonardo/WindowsNT-- Target :-- Dependency : ieee.std_logic_1164,ieee.std_logic_unsigned--------------------------------------------------------------------------------- Description: Single Port memory--------------------------------------------------------------------------------- Copyright (c) 2000 Jamil Khatib---- This VHDL design file is an open design; you can redistribute it and/or-- modify it and/or implement it after contacting the author-- You can check the draft license at-- http://www.opencores.org/OIPC/license.shtml--------------------------------------------------------------------------------- Revisions :-- Revision Number : 1-- Version : 0.1-- Date : 12 May 1999-- Modifier : Jamil Khatib (khatib@ieee.org)-- Desccription : Created-- Known bugs :-- To Optimze :--------------------------------------------------------------------------------- Revisions :-- Revision Number : 2-- Version : 0.2-- Date : 19 Dec 2000-- Modifier : Jamil Khatib (khatib@ieee.org)-- Desccription : General review-- Two versions are now available with reset and without-- Default output can can be defined-- Known bugs :-- To Optimze :--------------------------------------------------------------------------------- Revisions :-- Revision Number : 3-- Version : 0.3-- Date : 5 Jan 2001-- Modifier : Jamil Khatib (khatib@ieee.org)-- Desccription : Registered Read Address feature is added to make use of-- Altera's FPGAs memory bits-- This feature was added from Richard Herveille's-- contribution and his memory core-- Known bugs :-- To Optimze :-------------------------------------------------------------------------------library ieee;use ieee.std_logic_1164.all;use ieee.std_logic_unsigned.all;--------------------------------------------------------------------------------- Single port Memory core with reset-- To make use of on FPGA memory bits do not use the RESET option-- For Altera's FPGA you have to use also OPTION := 1entity Spmem_ent isgeneric ( USE_RESET : boolean := false; -- use system resetUSE_CS : boolean := false; -- use chip select signalDEFAULT_OUT : std_logic := '1'; -- Default outputOPTION : integer := 1; -- 1: Registered read Address(suitable-- for Altera's FPGAs-- 0: non registered read addressADD_WIDTH : integer := 3;WIDTH : integer := 8);port (cs : std_logic; -- chip selectclk : in std_logic; -- write clockreset : in std_logic; -- System Resetadd : in std_logic_vector(add_width -1 downto 0); -- AddressData_In : in std_logic_vector(WIDTH -1 downto 0); -- input dataData_Out : out std_logic_vector(WIDTH -1 downto 0); -- Output DataWR : in std_logic); -- Read Write Enableend Spmem_ent;--------------------------------------------------------------------------------- This Architecture was tested on the ModelSim 5.2EE-- The test vectors for model sim is included in vectors.do filearchitecture spmem_beh of Spmem_ent istype data_array is array (integer range <>) of std_logic_vector(WIDTH-1 downto 0);-- Memory Typesignal data : data_array(0 to (2** add_width-1) ); -- Local data-- FLEX/APEX devices require address to be registered with inclock for read operations-- This signal is used only when OPTION = 1signal regA : std_logic_vector( (add_width -1) downto 0);procedure init_mem(signal memory_cell : inout data_array ) isbeginfor i in 0 to (2** add_width-1) loopmemory_cell(i) <= (others => '0');end loop;end init_mem;begin -- spmem_beh--------------------------------------------------------------------------------- Non Registered Read Address-------------------------------------------------------------------------------NON_REG : if OPTION = 0 generate--------------------------------------------------------------------------------- Clocked Process with Reset-------------------------------------------------------------------------------Reset_ENABLED : if USE_RESET = true generate-------------------------------------------------------------------------------CS_ENABLED : if USE_CS = true generateprocess (clk, reset)begin -- PROCESS-- activities triggered by asynchronous reset (active low)if reset = '0' thendata_out <= (others => DEFAULT_OUT);init_mem ( data);-- activities triggered by rising edge of clockelsif clk'event and clk = '1' thenif CS = '1' thenif WR = '0' thendata(conv_integer(add)) <= data_in;data_out <= (others => DEFAULT_OUT);elsedata_out <= data(conv_integer(add));end if;elsedata_out <= (others => DEFAULT_OUT);end if;end if;end process;end generate CS_ENABLED;--------------------------------------------------------------------------------------------------------------------------------------------------------------CS_DISABLED : if USE_CS = false generateprocess (clk, reset)begin -- PROCESS-- activities triggered by asynchronous reset (active low)if reset = '0' thendata_out <= (others => DEFAULT_OUT);init_mem ( data);-- activities triggered by rising edge of clockelsif clk'event and clk = '1' thenif WR = '0' thendata(conv_integer(add)) <= data_in;data_out <= (others => DEFAULT_OUT);elsedata_out <= data(conv_integer(add));end if;end if;end process;end generate CS_DISABLED;--------------------------------------------------------------------------------------------------------------------------------------------------------------end generate Reset_ENABLED;----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- Clocked Process without Reset-------------------------------------------------------------------------------Reset_DISABLED : if USE_RESET = false generate--------------------------------------------------------------------------------------------------------------------------------------------------------------CS_ENABLED : if USE_CS = true generateprocess (clk)begin -- PROCESS-- activities triggered by rising edge of clockif clk'event and clk = '1' thenif cs = '1' thenif WR = '0' thendata(conv_integer(add)) <= data_in;data_out <= (others => DEFAULT_OUT);elsedata_out <= data(conv_integer(add));end if;elsedata_out <= (others => DEFAULT_OUT);end if;end if;end process;end generate CS_ENABLED;--------------------------------------------------------------------------------------------------------------------------------------------------------------CS_DISABLED : if USE_CS = false generateprocess (clk)begin -- PROCESS-- activities triggered by rising edge of clockif clk'event and clk = '1' thenif WR = '0' thendata(conv_integer(add)) <= data_in;data_out <= (others => DEFAULT_OUT);elsedata_out <= data(conv_integer(add));end if;end if;end process;end generate CS_DISABLED;--------------------------------------------------------------------------------------------------------------------------------------------------------------end generate Reset_DISABLED;---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------end generate NON_REG;----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------REG: if OPTION = 1 generate--------------------------------------------------------------------------------- Clocked Process with Reset-------------------------------------------------------------------------------Reset_ENABLED : if USE_RESET = true generate-------------------------------------------------------------------------------CS_ENABLED : if USE_CS = true generateprocess (clk, reset)begin -- PROCESS-- activities triggered by asynchronous reset (active low)if reset = '0' thendata_out <= (others => DEFAULT_OUT);init_mem ( data);-- activities triggered by rising edge of clockelsif clk'event and clk = '1' thenregA <= add;if CS = '1' thenif WR = '0' thendata(conv_integer(add)) <= data_in;data_out <= (others => DEFAULT_OUT);elsedata_out <= data(conv_integer(regA));end if;elsedata_out <= (others => DEFAULT_OUT);end if;end if;end process;end generate CS_ENABLED;--------------------------------------------------------------------------------------------------------------------------------------------------------------CS_DISABLED : if USE_CS = false generateprocess (clk, reset)begin -- PROCESS-- activities triggered by asynchronous reset (active low)if reset = '0' thendata_out <= (others => DEFAULT_OUT);init_mem ( data);-- activities triggered by rising edge of clockelsif clk'event and clk = '1' thenregA <= add;if WR = '0' thendata(conv_integer(add)) <= data_in;data_out <= (others => DEFAULT_OUT);elsedata_out <= data(conv_integer(regA));end if;end if;end process;end generate CS_DISABLED;--------------------------------------------------------------------------------------------------------------------------------------------------------------end generate Reset_ENABLED;----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- Clocked Process without Reset-------------------------------------------------------------------------------Reset_DISABLED : if USE_RESET = false generate--------------------------------------------------------------------------------------------------------------------------------------------------------------CS_ENABLED : if USE_CS = true generateprocess (clk)begin -- PROCESS-- activities triggered by rising edge of clockif clk'event and clk = '1' thenregA <= add;if cs = '1' thenif WR = '0' thendata(conv_integer(add)) <= data_in;data_out <= (others => DEFAULT_OUT);elsedata_out <= data(conv_integer(regA));end if;elsedata_out <= (others => DEFAULT_OUT);end if;end if;end process;end generate CS_ENABLED;--------------------------------------------------------------------------------------------------------------------------------------------------------------CS_DISABLED : if USE_CS = false generateprocess (clk)begin -- PROCESS-- activities triggered by rising edge of clockif clk'event and clk = '1' thenregA <= add;if WR = '0' thendata(conv_integer(add)) <= data_in;data_out <= (others => DEFAULT_OUT);elsedata_out <= data(conv_integer(regA));end if;end if;end process;end generate CS_DISABLED;--------------------------------------------------------------------------------------------------------------------------------------------------------------end generate Reset_DISABLED;---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------end generate REG;end spmem_beh;-------------------------------------------------------------------------------