Category: Commodore

Commodore 64, Commodore Vic-20, Commodore Plus 4

23XX Adapter

I’ve been trying to repair a VIC-20 with missing ROM’s. Unfortunately the original ROMS are getting more and more difficult to find and if you do find them they are way overpriced. Luckily with a few mods you can use newer EEPROMs or EPROMs like the 27C256 which are still available and cheap enough from …

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Commodore 1541 Troubleshooting

Trying to fix my first 1541 which I got off eBay.  Turning the 1541 on while not connected to the C64, the green LED comes on then the red LED and after 2 seconds it turns off. The spindle however keeps on spinning. Also no moment on the head.  Checked the 12V and 5V. Both …

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Commodore Plus 4 PCB 310162 Rev D

Commodore Plus 4 component layout

Commodore VIC-20 35K Expansion

After getting my Commodore VIC-20 working with SD2IEC  (Was a blown 7406 hex inverter) it’s now time to build a 35k expansion. Found a great write up on Ruud’s Commodore site.   A schematic is provided which gives the  VIC-20 35k of expansion memory using 62256  (32k x 8 RAM) and a 6264 (8k x 8 RAM)  …

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SD2IEC for Commodore 64

After winning a cheap bid on a Commodore 64 off eBay  the other day I’ve looked into  building a SD2IEC. The SD2IEC is a storage device using an SD card and interfacing with the IEC bus using a ATMega644 microcontroller. I used most of the information from 16 Bit Dust .  Looking at the schematic I already had …

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