is the ROM image for one of the most essential upgrades you can give a Commodore 64. Originally developed by CMD (Creative Micro Designs), it replaces the standard C64 Kernal to drastically improve disk access speeds and user convenience. Performance & Speed
Because it is a ROM replacement, it is always on. You don't need to load a "fast loader" program every time you turn the computer on. It makes the C64 feel like a much more modern machine. jiffydos-c64.bin
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