I am trying to generate waveform in verilog using the code below but the result aren't as expected.
initial begin
d = 1'b0;
#8 d <= 1'b1;
#15 d <= 1'b0;
end
Its initial value is 0(OK), at t=8, its 1(OK) but at t=23, its 0. Instead i want it to be 0 at t=15 relative to t=0 and not to t=8(i.e. previous statement).
Is there a way to do so? I have tried interchanging blocking and non-blocking assignments but no luck!
You could do this:
initial fork
d = 1'b0;
#8 d = 1'b1;
#15 d = 1'b0;
join
All the statements inside fork join will be executed concurrently.
Or you could do this:
initial d = 1'b0;
initial #8 d = 1'b1;
initial #15 d = 1'b0;
Clearly, the three initial blocks will be executed concurrently.
If you really wanted to schedule 3 events from procedural (sequential) code, then you could do this:
initial begin
d = 1'b0;
d <= #8 1'b1;
d <= #15 1'b0;
end
This uses intra-assignment delays together with non-blocking assignments.