Re: [myhdl-list] Simulation control

[Henry G. <he...@ca...>]

On 05/04/15 23:22, Juan Pablo Caram wrote:
> The problem is that I might need to stop for different signals, and 
> having them all call do_things() makes having a centralized control of 
> the mixed-signal simulation environment very complicated. On top of 
> this, how can I know them "time" at which the signal toggle inside the 
> "logic()" function"? I would need that to determine for how long to 
> run the analog simulation.
>
> Even worse, what if "clk" came from the analog simulation... I would 
> have to wait for each analog run complete to know when to toggle it, 
> and then manually toggle it. Here, the myhdl simulation would run 
> "behind".
>
> For short, I don't think I can implement the control of the whole 
> system from a single "do_things()" function. What do you think?

It's not totally clear to me what you're trying to do, but I'm yet to be 
convinced it isn't possible, and certainly yet to be convinced that 
having programmatic access to a debugging layer would be better than 
doing it all inside MyHDL.

You have a stateful spice simulator in a myhdl simulator. The myhdl code 
flips signals as desired until it needs to wait on the simulator doing 
something, then it blocks until the spice simulator reaches a suitable 
state and allows it to continue (let's say, when the virtual ADC flips a 
bit). Presumably you have inputs and outputs to your spice model? At 
some point, surely, you need virtual ADCs and DACs, so you're pretty 
limited in terms of directionality? In which case, you can set inputs as 
you wish and then block on outputs (or output sets).

I don't see the problem with clk - in your clock driver, you just block 
until the spice simulator has moved to the correct state.

Are you trying to do your myhdl logic in an asynchronous way? Or do you 
want sub-cycle times to be somehow meaningful between spice and myhdl (I 
don't have any idea what this could be)?

If you need to run the spice model and the myhdl simulation 
concurrently, you can do so in different threads.

cheers,

Henry