SP-808 Rosetta Looper OS

Build scripts patch your own decoded copy of Roland's 1.05 update and write an SP808.PRG that the unit installs from its Zip disk or from a ZuluIDE SD card emulating one. The result adds a boot animation, a new home menu, an MPC mode where a pad is selected and then sampled into, and a keyboard mode that plays one sample pitched across the pads and a MIDI keyboard with eight extra voices plus the four stock ones. The looper mode (pad layers, overdub, undo and clear) has only been tested in an emulator. The repository also holds a homemade H8S disassembler, assembler and emulator, and a DSP decoder. The author calls it a parked preview from October 2026. The builds are based on the SP-808 OS, so installing one on an SP-808EX turns it into a non-EX.

Needs Roland's official SP808v1050.zip, which you supply. Run the decode and build scripts, add the resulting SP808.PRG to your Zip or ZuluIDE disk image, then power on with the disk in and answer YES to the update prompt. Back up the disk image first. The boot ROM has a MIDI recovery mode that the OS cannot overwrite. Built images should not be shared.