Storage, saves and memory¶

Flash layout¶

The VGC Zero has 16 MB of flash, split three ways:

Region	Contents
0–256 KB	the loader (ChiliChip OS firmware)
256 KB–12 MB	installed `.blit` games, in 64 KB blocks; the home screen is the first
12–16 MB	a FAT file system, shown on your computer as the CHILICHIP USB drive

Games run straight from flash (execute in place). The RP2350's address translation maps whichever game is running to the same address, so every .blit is built for one fixed location and can be installed anywhere.

The USB drive¶

The 4 MB drive holds everything that changes:

CHILICHIP/
├── .system/
│   └── settings.bin     # brightness, volume, screen sleep
├── .blit/
│   └── <game title>/
│       ├── save0        # write_save(data, 0)
│       └── save1        # write_save(data, 1)
└── game.blit            # copied here to install, then removed

Your game can also read and write its own files on the drive with the Files API.

Saves¶

write_save() writes slot n to .blit/<title>/save<n>, where <title> is the title from your metadata.yml. Because saves live on the drive rather than with the game:

reinstalling or updating a game keeps its saves;
players can back up a game's saves by copying its folder;
changing your game's title loses access to the old saves, so keep the title stable.

When a game is deleted from the home screen and has saves, the console asks whether to delete them too.

The console has a hard power switch, and switching it off can't be caught. Save at checkpoints as well as in on_quit. See Saving progress.

RAM¶

The RP2350 has 520 KB of RAM. The loader keeps the first 64 KB; the running game gets the rest:

Region	Contents
0–64 KB	loader data, its heap, and the 32 KB core 0 stack that games run on
64–512 KB	the running game: its code that must run from RAM, data, heap, and the framebuffer

So a game has 448 KB for everything, including its framebuffer: 32 KB in hires mode, 8 KB in lores. Your stack is 32 KB, the same as a standalone build.

A .blit built against an SDK from before the loader's RAM grew to 64 KB expects games to start at 32 KB, and must be rebuilt.

See Performance and memory for how to keep within these limits.