Character ROM Pinouts?
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Character ROM Pinouts?
My Vic has a 901460-03 character ROM chip. Where can I find a pinout diagram for this chip? I've only seen mentions of a 2332 chip on this site. Why is the 901460-03 pinout so hard to find??
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Mike
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Re: Character ROM Pinouts?
The character ROM of the VIC-20 is a programmed 2332 chip.
901460-03 is just the part number assigned by Commodore after the data had been programmed.
Here's the data sheet: mos_2332_rom_feb_1980.pdf from archive.6502.org
Note: CS1 and CS2 could be specified either as low- or high-active during manufacture, and are both low-active with the 901460-03. A 2732 (access time <= 300 ns) with an adapter socket (swapping pins 18 and 21) can thus work as substitute, see: Request help on replacing 2332 4Kx8 Char ROM -> Fixing a VIC.
901460-03 is just the part number assigned by Commodore after the data had been programmed.
Here's the data sheet: mos_2332_rom_feb_1980.pdf from archive.6502.org
Note: CS1 and CS2 could be specified either as low- or high-active during manufacture, and are both low-active with the 901460-03. A 2732 (access time <= 300 ns) with an adapter socket (swapping pins 18 and 21) can thus work as substitute, see: Request help on replacing 2332 4Kx8 Char ROM -> Fixing a VIC.
Re: Character ROM Pinouts?
Thanks Mike. You confirmed my suspicion about the 2332. Turn out my char ROM was fine anyway. I desoldered it, tried it another machine and all was well. Means my 6561 is probably dead 