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[/] [idea/] [trunk/] [behavioral/] [main control/] [counter.vbe] - Rev 9
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-- VHDL data flow description generated from `counter`
-- date : Wed Mar 21 13:35:50 2001
-- Entity Declaration
ENTITY counter IS
PORT (
ck : in BIT; -- ck
i : in BIT; -- i
reset : in BIT; -- reset
o : out BIT; -- o
vdd : in BIT; -- vdd
vss : in BIT -- vss
);
END counter;
-- Architecture Declaration
ARCHITECTURE VBE OF counter IS
SIGNAL current_state : REG_VECTOR(2 DOWNTO 0) REGISTER; -- current_state
SIGNAL current_state_s4 : BIT; -- current_state_s4
SIGNAL next_state_s4 : BIT; -- next_state_s4
SIGNAL current_state_s3 : BIT; -- current_state_s3
SIGNAL next_state_s3 : BIT; -- next_state_s3
SIGNAL current_state_s2 : BIT; -- current_state_s2
SIGNAL next_state_s2 : BIT; -- next_state_s2
SIGNAL current_state_s1 : BIT; -- current_state_s1
SIGNAL next_state_s1 : BIT; -- next_state_s1
SIGNAL current_state_s0 : BIT; -- current_state_s0
SIGNAL next_state_s0 : BIT; -- next_state_s0
SIGNAL next_state : BIT_VECTOR(2 DOWNTO 0); -- next_state
BEGIN
next_state(0) <= (next_state_s0 OR next_state_s3 OR next_state_s4);
next_state(1) <= (next_state_s0 OR next_state_s4);
next_state(2) <= (next_state_s2 OR next_state_s3 OR next_state_s4);
next_state_s0 <= ((current_state_s0 AND NOT(i)) OR (
current_state_s1 AND NOT(i)) OR (current_state_s2 AND NOT(i)) OR
(current_state_s3 AND NOT(i)) OR (current_state_s4
AND NOT(i)));
current_state_s0 <= (NOT(current_state(2)) AND current_state(1));
next_state_s1 <= (current_state_s0 AND i);
current_state_s1 <= (NOT(current_state(2)) AND NOT(current_state(1)));
next_state_s2 <= (current_state_s1 AND i);
current_state_s2 <= (current_state(2) AND NOT(current_state(0)));
next_state_s3 <= (current_state_s2 AND i);
current_state_s3 <= (NOT(current_state(1)) AND current_state(0));
next_state_s4 <= ((current_state_s3 AND i) OR (current_state_s4
AND i));
current_state_s4 <= (current_state(2) AND current_state(1));
label0 : BLOCK ((NOT((ck'STABLE)) AND NOT(ck)) = '1')
BEGIN
current_state(0) <= GUARDED (next_state(0) OR reset);
END BLOCK label0;
label1 : BLOCK ((NOT((ck'STABLE)) AND NOT(ck)) = '1')
BEGIN
current_state(1) <= GUARDED (next_state(1) OR reset);
END BLOCK label1;
label2 : BLOCK ((NOT((ck'STABLE)) AND NOT(ck)) = '1')
BEGIN
current_state(2) <= GUARDED (next_state(2) AND NOT(reset));
END BLOCK label2;
o <= (current_state_s4 AND NOT(reset));
END;