Commodore 64 128KB cartridge

This project is aimed at creating a C64 cartridge that contains up to 128 Kilobytes of information. Since the Commodore could only access 8KB or 16KB at a time, the cartridge allows for switching out several 8KB banks mapped to the single 27C010 EPROM. It's interface is roughly the same as the Magic Desk I cartridge's circuit design.

This video showcases this cartridge design's versatility by loading the classic game, M.U.L.E., from cartridge (in two stages).

For more information, go to http://www.puzzud.com.

Category:

Gaming

Tags:

• commodore 64
• c64
• cartridge
• m.u.l.e.
• mule

[BagoZonde]

@puzzud

I've been really interested in cartridge development for a few months now and together with my friend we've built a clone of Black Box 8 cartridge but now we're looking for something more than 32k. Few weeks ago we found some schemes for Magic Desk but they were for 2 EPROMs and I have no idea how to make it on one 27c010 now, I'm just a programmer so it can take a little more time :).

[puzzud]

@BagoZonde I'm just a programmer. This project is my first real electronics endeavor. Between Sam Appelman's schematic and Nicholas Coplin's reversal of Magic Desk I, I pieced things together. In my design, IO1 and the system clock is sent through a NOR gate to drive the state of the flip flops that control the highest address bits of the EPROM. I'll get my schematic on my website at one point.

[BagoZonde]

Really nice work. Tell me if there's possibility to switching banks forward and backward? And which method of switching this cartridge using (any compatibility with Vice emulator)? Mule-credible stuff :)

[puzzud]

@BagoZonde Thanks. The interface is nearly identical to the Magic Desk I cartridge, which is supported by VICE and CCS64.

I prototyped the cartridge software and tested with VICE before I started physically putting the circuit together. I wrote a utility to build the .CRT file and the binary I load into the EPROM.

In general, as long as the code that switches banks does not reside on the bank when executed, any order of bank switching is possible.

[vachthuegen]

mule-icious! nice work with the pcb and breadboard