Hello,
We can generate clock in this many ways.
bit clk = 0;
clk = !clk;
or clk = ~clk;
or clk +=1;
what difference make this three statements. is there any changes at hardware level?
Thanks in Advance.
In reply to Dhanesh_Padia:
I use
- initial forever #10 clk=!clk;
The ! is the logical not or inversion operator of its value and produces a value of 1 0r 0, true or false (no vector)
- The ~ is bitwise invert operator. Thus on a vector of v=101, the ~v has the value 010.
Obviously, for a 1 bit vector, the ~ and the ! produce the same results.
However, they have different connotations. I prefer the ! (meaning invert, true/false result, of the value of the vector)
- The clk +=1; works, but does not make sense, and adder?
- *is there any changes at hardware level?*
Actually, the clock is never synthesized and is generated externally via a crystal clock oscillator with very tight tolerances on the frequency.
Ben Cohen
http://www.systemverilog.us/ ben@systemverilog.us
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See Paper: 1) https://verificationacademy.com/forums/systemverilog/vf-horizonspaper-sva-alternative-complex-assertions
2) http://systemverilog.us/vf/SolvingComplexUsersAssertions.pdf