synopsys design compiler -- commands to set test cases

[linny_chen]

There is one command in synopsys design compiler called "set_case_analysis", which can set some constant test case on certain ports, without optimized away components influenced by this constant setting. But "set_case_analysis" can only set signal values like 0, 1, rising edge and falling edge to the test ports. Could anyone tell me if there is such similar commands which could set values like Z, -, U, X etc? Thanks a lot!

 

[ljxpjpjljx]

why you want to do so ?

 

[linny_chen]

Hi, friend,

I have some multiplexers inside my circuit. I would like to set a value on the selection port of multiplexer to guide Design Compiler when it is calculating the critical path. For some multiplexers I want neither of the input to be selected.