--- Nicolas Welte <email@example.com> wrote: > Ethan Dicks wrote: > > ASSY 326298 > > The ASSY number is the key to identify each board. The C64 service > manual (also online on funet, I think) lists this number as 'original > board'. > > The schematic of the original board suggests that there is a PAL/NTSC > jumper, it should be a jumper wire like in the version A board that can > be put either on location E2 or E3. The board layout shows an empty > space near U29 in the video cage, maybe this is where the jumpers are. Indeed there is. I missed the legend because part of it is obscured by a large cap, C33. > Maybe they made a last minute change in the C64 for unknown reasons, and > the video chip and the ROM were left configured for 1MHz. The only crystal in this box is the 14.31818 MHz one that you would expect. > And I think the VIC-20 runs at significantly higher clock speed, > perhaps 1.2 MHz. I forgot ;-) 1.0Mhz, IIRC. > It's a pity that you don't have your original C64 anymore. There's > always the search for early chips to explore funny bugs. We didn't have to search for bugs... I got bit every time the machine got warm. I used to save every five minutes. > I think Andreas Boose wanted to know once if the reset bit, that is > disabled in all known VIC-II chips is perhaps active in very early > versions. Perhaps you could try it on your machine? Sure... give me some more details. I can write a quick BASIC program if I know what addresses you want wacked. How does it behave in later C-64's? -ethan _________________________________________________________ Do You Yahoo!? Get your free @yahoo.com address at http://mail.yahoo.com - This message was sent through the cbm-hackers mailing list. To unsubscribe: echo unsubscribe | mail firstname.lastname@example.org.
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