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The first revision of a brand new GCart variant just went out for manufacturing. Meet GCart Games — the cartridge that does exactly what the name says, and not much more. And that's the whole point.
The Lineup Grows
The GCart family now looks like this:
- GCart DCNT — Dirt Cheap, No Thrills.
- GCart FUSION — The best of Jr and MX, fused into one board.
- GCart Games — This one. Purpose-built. Lean. Cheap.
- GCart Cartridge — One FLASH/EPROM memory with optional 3k memory.
What's On It?
Up to 32 MByte of NOR FLASH. That's storage for up to 4096 cartridge images at 8K each. Pick a game, boot it, play it. That's the workflow. No ceremony.
Full software-controlled memory expansion. The VIC-20's memory map is notoriously fragmented, and different software expects different configurations. GCart Games handles this in software — no jumpers, no DIP switches, no pulling the cartridge to flip something. The expansion configures itself to match what the loaded program needs.
That's it. No SD card. No RTC. No MIDI synth. Just flash, RAM expansion, and a way to boot. It does the thing, and it does it cheaply.
The Part Count is... Small
This is where it gets interesting from a design perspective. Open up a GCart Games and you'll find a remarkably sparse board. The heavy lifting is done by just two GreenPAK programmable logic ICs:
GreenPAK #1 handles the BLK decoding — the address logic that maps cartridge ROM blocks into the VIC-20's expansion memory space.
GreenPAK #2 is the ambitious one. It implements a full 65C02 parallel bus to serial SPI FLASH bridge, including auto-boot logic so the cartridge can boot from BLK5 directly out of serial NOR FLASH at power-on.
Will it fit? Honestly — it's going to be tight. GreenPAK devices are remarkably capable for their size, but squeezing a parallel-to-SPI bridge with auto-boot sequencing into one is pushing right up against the logic resource limit. But that's part of the fun. If it works, the BOM stays tiny and the cost stays low. If it doesn't, well, that's what revision A.2 is for.
Same Shell, Smaller Board
Mechanically, GCart Games shares the same enclosure design as the other three GCart cartridges — GCart Cartridge is the exception, being noticeably smaller. So if you already have a GCart on your desk, you know what this one looks and feels like. Familiar form factor, very different internals.
What's Next?
Boards are on order. Once they arrive, I'll populate a prototype and find out if that second GreenPAK is as clever as I need it to be. Updates to follow — success or spectacular failure, either way it'll be worth writing about.