Re: [myhdl-list] debugging Cosimulation with Icarus Verilog

[Günter D. <dan...@we...>]

Jan Decaluwe wrote:
...
> 
> Maybe with the bug fix you can use the assignment that was commented out,
> and perhaps that fixes it?
> 
>    // icarus stops on the following line but shouldn't
>    // cb_data_s.value = &value_s;
>    cb_data_s.value = NULL;
> 

Yes, that part works now. But unfortunately does not fix the toVerilog
test errors.

Some of the toVerilog tests failures are caused by the callback at
simulation time 0. The problem is that the callback at time 0 returns a
value 'x' for the signal. The Cosimulation class does not like that and
due to the exception in the Cosimulation._get(self) function an
intbv(None) instance is returned.

So the solution specific to Icarus would be to register the first
cbValueChange call back at simulation time 1. That could actually be
used for all simulators, as the others do it anyway that way.

BTW, I noticed the change is already part of the latest Icarus Verilog
development snapshot 2008-08-30.

Guenter