Fixed build issue in tester, added set_step_callback to Python bindings.

[andrastantos]

Hello!

Thanks for this great project!

I intend to use your simulator as a reference implementation to compare it to my work, but in order to do so, I needed to add a new Python callback option to hook on_step.

Would you mind merging the change into your own repo?

Thanks,
Andras

[kosarev]

@andrastantos Hi Andras. Thanks for using this. Do I take it right that your aim is merely to stop on every executed instruction and examine the state? If so, we might prefer to do this via events so run() could just return control on every step.

[kosarev]

@andrastantos Hi Andras, please let me know if just marking all addresses as breakpoints would work for you. I'm trying to grasp the real use case after this patch. There may be a better approach.

[andrastantos]

Kosarev, My project is a Python to Verilog library. That is, it allows you to write Python programs in a certain way that can be turned into Verilog and synthesized into an FPGA. For this project, I thought it would be fun to write a Z80 processor as a test-case. For verification purposes though I need a Z80 reference implementation, which is where your project comes in. I intend to use your Z80 model to verify my implementation against. The idea would be something along the lines of running the two Z80 versions in lock-step, checking that all the register values/flags are identical between the two, and that the same memory reads and writes are issued from both instances (there's some complexity around interrupts, but that can be addressed later). I think your python bindings already allow me to inspect the register contents, and hook memory reads/writes. So, what's left is to get the two cores synchronized. I'm thinking at this point it's probably better if I had the ability to single-step your core from my test-bench, rather than the other way around. My previous pull-request doesn't achieve this though so, I think you can ignore this change. Setting every address as a break-point is one way of achieving my goal, though it seems a bit heavy-handed. I have another local change that changes 'ticks_per_frame' to be a member variable instead of a constant, and makes it accessible from Python. This allows me to set it to '1' which effectively allows me the single-step the core. I'm not sure if that's the best way though. Andras

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On 11/11/2020 11:50 AM, Ivan Kosarev wrote: @andrastantos <https://github.com/andrastantos> Hi Andras, please let me know if just marking all addresses as breakpoints would work for you. I'm trying to grasp the real use case after this patch. There may be a better approach. — You are receiving this because you were mentioned. Reply to this email directly, view it on GitHub <#4 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AIPWQ4YRPVLCONIC22JJPPTSPLTITANCNFSM4TFOBDYA>.

[kosarev]

@andrastantos Hi Andras, 2cd8d75 makes it possible to limit the number of ticks to run. It also provides some simple single-stepping example. Would love to know if it works for your case. Thanks.

[kosarev]

All the requests related to this are now addressed elsewhere. Closing this. Thanks.