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PostPosted: Sat Apr 26, 2003 1:24 pm 
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This might sound like a really screwed up question, but does anyone know of a 6510-emulator written in 6510 machine code? I don't wanna write one if it really exists.

If someone feel they need an explanation, here it is:
I need to be able to test automatically generated code (on a c64) before actually letting it lose on the real CPU, to make sure it behaves. (No out of bounds memory access and only execution of permitted opcodes for example).

Anyone?

/Autoboy


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PostPosted: Tue Dec 30, 2003 3:54 pm 
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You can let the CPU do most of the decoding for you, after you do as much decoding as necessary to validate the instruction (and possibly modify it). Once it's validated/modified, copy it to an execution area in RAM which restores the processor state, has a NOP-padded slot for the instruction, then saves processor state again. I've used this in a couple of debugger/monitors on other 8-bit CPUs for their single-step mode and even on the PowerPC processor which is quite a different beast than the 6502.


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PostPosted: Tue Dec 30, 2003 7:00 pm 
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autoboy wrote:
This might sound like a really screwed up question, but does anyone know of a 6510-emulator written in 6510 machine code? I don't wanna write one if it really exists.

Check out Cameron Kaiser's KIMplement:
http://www.floodgap.com/retrobits/kim-1/

It looks like he's done what you'd like to do, perhaps he'll share his source code with you.

Regards,
Mike

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PostPosted: Tue Oct 31, 2023 4:33 pm 
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This is a really old necropost, but I figured it was worth tacking on: the plan is to opensource 6o6 with the next release ("1.0") of the KIMplement, which will also be opensourced now that I'm satisfied with code quality, years and years later. 6o6 is the "6502-on-6502" virtualizer that it uses.

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PostPosted: Tue Oct 31, 2023 6:59 pm 
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Sounds like a good development!


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PostPosted: Fri May 03, 2024 7:02 pm 
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Joined: Wed Jan 03, 2007 3:53 pm
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Forgot to post it to this thread!

Discussion: https://oldvcr.blogspot.com/2024/04/vir ... 6-and.html
Code: https://github.com/classilla/6o6

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