Category: Marc-Jano Archive

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ROM updates & working with EPROMs

[Archived from Peter Schepers’ site]
The ROM’s in the C64 and the original 1541 models are 24 pin and are not directly pin compatible with burnable 2732 or 2764 EPROMS. In order to upgrade to a newer ROM revision or change the ROM to something else and use either a 2732 (for the character set) or 2764 (for kernal/DOS) EPROM, a socket adapter must be built. See here for detailed instructions on how to build one.

archives / commodore / Marc-Jano Archive

Making Commodore 64 ROM Socket Adapters

Socket adapters are required on the original C64 and 1541 models when replacing the existing 24-pin ROM with a 28-pin EPROM, like a 2764 or larger. They are also needed if you want to replace a 2764 with a larger 27128, a 27128 with a 27256 or a 27256 with a 27512. All of these adapters are covered here.