Working visual simulation of a 6502 chip

[bommy261]

http://visual6502.org/JSSim/index.html

Having had many courses in transistors, i found this pretty cool.

 

[DaveSimmons]

I'll have to play with this later, the 6502 was the first CPU I learned assembly for, for Atari 800 and C=64 coding.

Edit: Like this

(Yes, I'm old )

 

[Train]

Pretty cool, I always wondered if newer tech could visualize an entire CPU (of older tech)

 

[Leros]

Pretty cool, I always wondered if newer tech could visualize an entire CPU (of older tech)

I don't see why not. Some of the older processors has ~10,000-100,000 transistors. It shouldn't be too hard to simulate that with a modern processor.

 

[Train]

I'll have to play with this later, the 6502 was the first CPU I learned assembly for, for Atari 800 and C=64 coding.

Edit: Like this

(Yes, I'm old )

I actually wrote my own assembler for the C=64.

 

[Train]

I don't see why not. Some of the older processors has ~10,000-100,000 transistors. It shouldn't be too hard to simulate that with a modern processor.

The bottleneck at this point is more the screen real estate required to show anything useful and/or traceable

 

[Leros]

The bottleneck at this point is more the screen real estate required to show anything useful and/or traceable

An algorithm to zoom in or out wouldn't be too hard. I can think of several ways to have different levels of zoom.

Signals can easily be logged, although the log file size would be rather large.

 

[Colt45]

Wasn't 6502 era stuff designed on paper anyway?

 

[Train]

An algorithm to zoom in or out wouldn't be too hard. I can think of several ways to have different levels of zoom.

true.

Signals can easily be logged, although the log file size would be rather large.

Why log it? Just keep a track of what the input was. You can "catch up" from any starting point to any point down the road pretty dang quickly. IIRC it was a 1.5 mhz CPU, lets say a 3 ghz multi core CPU today, would be able to do hours worth of 6502 crunching in a matter of seconds

 

[Leros]

true.



Why log it? Just keep a track of what the input was. You can "catch up" from any starting point to any point down the road pretty dang quickly. IIRC it was a 1.5 mhz CPU, lets say a 3 ghz multi core CPU today, would be able to do hours worth of 6502 crunching in a matter of seconds

You could argue that. I guess it would depend on what kind of analysis you want to run later.

 

[Train]

You could argue that. I guess it would depend on what kind of analysis you want to run later.

but then as soon as I clicked submit I thought of the random function. There would probably at least have to be logged randoms (unless the 6502 random was THAT predictable)

 

[Leros]

but then as soon as I clicked submit I thought of the random function. There would probably at least have to be logged randoms (unless the 6502 random was THAT predictable)

It would depend how the random function was seeded and how often it was seeded (once or for each call?). Assuming the random function was seeded based off CPU time, you could reconstruct the CPU time during your re simulation.