Design Recipes for FPGAs
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additional delays due to the technology library gate delays, poten-
tially resulting in glitches or hazards. An example of a multiple
gate combinatorial architecture using internal signal declarations
is given below:
architecture behavioural of test is
signal int1, int2 : bit;
begin
int1 <= in1 and in2;
int2 <= in3 or in4;
out1 <= int1 xor int2;
end architecture behavioural;
Process: basic functional unit in VHDL
The process in VHDL is the mechanism by which sequential state-
ments can be executed in the correct sequence, and with more than
one process, concurrently. Each process consists of a sensitivity list,
declarations and statements. ...