[Iverilog-devel] How to get .fst dump file to update more frequently?

[<by...@nc...>]

> Hello,
> 
> I'm recently transitioned from .vcd to .fst output files and am happy with
> the saved disk space, but is there any way to get the .fst file written to
> disk more frequently?  I'd like to be able to update my waveforms every
> minute or so to make sure the simulation is functioning properly.
> Sometimes the .fst file just never gets written to disk until the
> simulation ends, or I have to ctrl-C break it and $finish prematurely to
> force the .fst file to be written.
> 
> Is there a better way?
> 
> Thanks,
> -Brian

Brian,

Looking in sys_fst.c, it appears that $dumpflush called periodically in your testbench at the end of some timestep should do what you want.  You'd have to make some timing measurements based on your cycles per second to update the waveforms as often as you want.  Note that the filesize will get bigger the more often you force flushes.

-Tony