Overclocking the 2600 with a WDC65c02

[Wickeycolumbus]

Got one of the PCBs assembled. It is pretty buggy and doesn't work every time, but it's a lot better than my previous attempt at a PCB which did not work at all. I suspect that the reset circuit could be one of the issues. I'm using the circuit from the original 2600 with an electrolytic cap, perhaps a ceramic would be a better choice. There are also some weird things going on, for example the demo seen running in post #21 won't launch at all.

 

The only thing that I could get running that I still had an EPROM of was a static screen with a line drawn with PF1. On the new PCB, it appears that the PF1 is shifted to the left, about where you would think PF0 should be (it appears where it should be on the original unit). No idea why this is happening. I am using a crystal oscillator slightly different from what the original schematics have (3.579550 mHz over the original 3.579575 mHz), perhaps this is an issue?

 

Here is the assembled board next to a standard 2600 cartridge for size comparison:

 

 

Here is the PF display I mentioned. The D7 bit of PF1 appears to be displayed where PF0 should be.

 

 

 

Time to write/test some new software to try to iron out the bugs. Stay tuned

[Andromeda Stardust]

When you get things going, it would be fun to test some older VCS games like Combat and Video Pong and see how badly they break. Anything that updates the TIA during scanlines will be broken by default, so only the earliest games would run, if at all. I'm exited to see what you can do with it...