Case-statement in synchronous process.

[khaila]

synchronous process with non blocking

when I have a case statment in a synchronous process, can I leave WHEN OTHERS with no value???

In Aynchronous process I should insert values to make sure that no latch will be produced. but what about synchronous process???

 

[Mikal120]

Yes, I think so . It will hold the last value if case-statement was not met.

 

[Fawad Elahi]

can you please repeat your question in easy language.i do not get it

 

[jkang]

No. A synchronous process will simply create a register. As such, there is no requirement for branches to be "complete". Be careful if you're relying on ordered assignments, though. For instance, the following:

signal1 = 1'b0;
case(condition_sig)
1'b0:
signal1 = 1'b1;
endcase

Some synthesizers (particularly if you have the synopsys_full and synopsys_parallel options on) will not do preemption and simply ignore the blocking statements if this is a clocked block. That is, it will treat the blocking assignment as non-blocking.

To avoid this, a rule of thumb is to always use non-blocking assignments in registered blocks.

 

[vlsi_freak]

Hi..

You can write as

when others=>
null;

end case;l

Hope it helps

Thanks