Capture 6560 Data From Cart Port

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Radical Brad
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Re: Capture 6560 Data From Cart Port

Post by Radical Brad »

Indeed, it would be a lot of work to make this little experiment versatile enough to more than echo a basic text screen with colors. Something like a demo with raster effects would require a very complete core inside the FPGA.

It would be an interesting project though. One day if I have nothing but time on my hands.
Probably easier just to continue with an actual 6560 replacement, which is what I started as another side project.

TRON was a security program gone amok, wasn't it?
Something like that seems to happen inside my modern PC once a week!
No wonder I am so devoted to bringing my VIC back as my main computer.

Brad

Mike wrote: I just stated the minimal requirements to pull off the trick as seen in the video. ;)

If you snoop more on what the 6502 produces as data traffic, you can surely improve on the model of the VIC-20 inside the FPGA, up to the point that the FPGA faithfully reproduces writes into the VIC registers: you'd need to emulate the instruction stream inside the FPGA to infer the missing address bits CA14 and CA15. Next you'd have to mirror the VIA chips, to account for any interrupts and I/O. People here are doing nice things by running VIC, CPU and VIAs in lock-step. :mrgreen:

At one point you have a complete model of the VIC-20 inside the FPGA, and then you'd have something like the current emulators like VICE achieve without a VIC-20 being there 'in person'. :)

Good luck!

Michael


P.S. you actually remember the original purpose of the TRON program in the movie? ;)
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Mike
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Re: Capture 6560 Data From Cart Port

Post by Mike »

Mike wrote:P.S. you actually remember the original purpose of the TRON program in the movie? ;)
RadicalBrad wrote:TRON was a security program gone amok, wasn't it?
Not at all. TRON fights for the users! 8)

Actually, TRON is described by its creator, Alan Bradley, as "a monitor program, capable of detecting any malign communication. If it detects a disallowed communication attempt, that one is aborted. It could even monitor the Master Control Program!" - and you know what happened in the movie. :mrgreen:

The MCP and Sark are the main villains and later - in TRON Legacy - CLU 2 takes that role.
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