Hi. Recently I decided to give my C64 a run with some of the newer demos (edge of disgrace ftw). Now I just got myself a 28" tv and those vertical lines that plague the 64C are quite bad on such a big screen. So I pull my breadbox out and try that. Much better picture but for some reason it can't make it to the second part of eod (or my other machines barring my main).
Now AFAIK the main reason why I can't just pop a 6569 into my main C64 is because there's no 12v supply. Now I have been going over the schematic and it seems all I need to do to get 12v is swap a 9v zenner diode for a 12v one (cant remember which one of hand) and I thought for the 9v supply to the SID I could just fit a regular 9v regulator running off the 12v supply, with the appropriate mods to the PCB to keep the SID fed with 9v and send the 12v to the VIC.
I had thought of adapting a breadbox pcb to take a 8580 SID (swapping capacitors and modding voltage lines etc.) But I can't figure why only one of my machines can play eod all the way through.
One other thing, anybody here know how effective it would be to swap the C64's dram for sram? (with appropriate interfacing logic) I have been toying with a idea for a simple (and relatively cheap) internal ram expansion.
Post by David Murray on Jan 5, 2009 23:46:29 GMT -5
I have several games that work on the 64C or a 128 but refuse to play on my original breadbox unit. I've posted on this topic before on comp.sys.cbm, but nobody has ever given a satisfactory answer. One of the games is Gianna Sisters. But I can't remember what the others are right off the top of my head. But there are obviously minor differences in the machines that can cause incompatibilities.