BMCoCo-Pi 0.1.0rc3 · Windows setup, Linux console and model downloads.

SD-card preparation and safety

Fresh installation erases the selected card

Treat a new card and a reusable card the same way: inspect the exact physical device, back up anything needed, then confirm erasure. Do not interpret an old drive letter, Linux device name or photograph as current device identification. The utility must reject system disks and busy/ambiguous targets, and recheck identity/capacity immediately before any destructive operation.

The setup utility creates one aligned MBR primary FAT32 partition labelled BMCOCO, spanning usable card capacity. No Raspberry Pi OS, ext4 partition, swap or Linux root filesystem is needed. Model-specific boot files stay at the card root; ROMs, profiles and media go beneath bmcoco/.

Quick format, not a full-card write

Create partition/filesystem geometry for the actual card, then copy only the installation files. A 128GB card does not need 128GB of installation data. Do not zero-fill unused space or hash the entire physical card. Verify all installed files, resulting capacity and filesystem consistency instead. Quick formatting is not secure erasure of former contents.

This design uses available space immediately. There is no first-boot growth implementation. A small .img written to a larger card does not automatically grow its partition and filesystem; simply extracting a ZIP onto an arbitrary exFAT/NTFS card is not a substitute for preparation either.

Fresh quick-format installation passed on the tested 32GB card using Linux and the packaged Windows helper, including geometry/file readback and safe release. This does not validate every capacity, reader or old partition layout. Windows refuses GPT/unsupported layouts rather than erasing them blindly.

Maintenance is a different operation

Adding missing profiles/media must not repartition, format, overwrite differing files, replace ROMs or change saved startup/display settings. An update must show exactly what will change and provide recovery. Kernel updates use their own staged verification/Apply/rollback workflow, not bulk copying over a live card. Do not remotely resize the Pi's live volume through file commands.

Completion, failure and power

Only remove the card after every required file passes complete readback, filesystem/geometry checks succeed and sync/unmount completes. Never pull the reader during a copy or remove Pi power during an update/write. If the process fails, keep its report and treat the card as not ready, even if some files are visible. Quick format/copy is not an atomic transaction and a power failure can damage FAT metadata. Preserve owner ROMs and media on the PC for recovery.

Guide edition: November 2, 2026.