Re: [myhdl-list] StopIteration caught?

[Jan D. <ja...@ja...>]

Neal Becker wrote:
> My stimulus will read from the input vectors using .next().  Eventually 
> raising StopIteration.  It appears this is being caught?  And, does not stop 
> the simulation.  Is this the expected behavior?

Yes.

A MyHDL simulation consists of a number of "simultaneously" running
generators. If StopIteration weren't caught, the simulation would stop
as soon as one of them runs out of steam. Instead, a simulation has
to run as long as some generator remains active.

Of course, the problem then is that you can easily create simulations
that run forever. Not unlike VHDL and Verilog, you have to make sure
that the simulation stops when you know you're done. For this reason,
StopSimulation is explicitly exported by myhdl and it is the intention
that users raise it.

> I guess I need to catch StopIteration myself, and raise StopSimulation if I 
> want to stop?

Yes. Note that you would probably have to raise StopSimulation also in other
cases, for example when using a for-loop instead of a generator.
Otherwise the simulation runs as long as there are events e.g.
from a clock generator.

Alternatively you can give a time duration to Simulation.run().

Jan

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