What does #`DEL mean in Verilog?

Question

I saw some statements in the form of below. What does #`DEL mean here? I cannot find its meaning easily because it contains a special character.

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Answer 1

The code in question delays the assignment by some amount. The #`DEL (can't use inline coding because of the backtick) has 3 parts. First, the # indicates that this is a delay statement. Next, the backtick (the character underneath the ~) indicates a preprocessor definition in Verilog; somewhere in the code you're compiling you will have something along the following lines:

`define DEL 1ns

Where 1ns might be any time value, which will be the delay. We should be clear here that there should be a backtick (under the ~) before DEL, whereas 32'b0 uses a single quote.