OpenCart64

Fig. 1: OpenCart64

OpenC64Cart is an Open Hardware Cartridge for the Commodore 64. It only supports 8 KB ROM images.

OpenC64Cart is designed to accept a 27xxx style (E)EPROM and can support up to 8 8kb cartridge images with a 27512-style (E)EPROM.

Depending on the size of your (E)EPROM, you can configure the jumpers to use a specific image.

IMPORTANT: ALWAYS TURN YOUR C64 OFF BEFORE MOVING THE CONFIGURATION JUMPERS.

When flashing the contents, make sure that every file is exactly 8192 bytes long and just concatenate them. Then use the following table to set the jumper configuration for your image of choice:

Image # A13 A14 A15
1 L L L
2 H L L
3 L H L
4 H H L
5 L L H
6 H L H
7 L H H
8 H H H

You will also need to configure the ROM and EXROM/GAME jumpers for the chosen image, according to the following table:

Mode ROM Game ExROM Notes
ROML LO Open Close Most Common ROM
UltiMax HI Close Open Originally Used By MAX Machines, Will Bypass Kernal ROM (Dead Test)

Note that with this cartridge GAME and EXROM must NEVER closed at the same time.