Demul Mpr 21931 — Ic501 Repack

mpr-21931.ic501 (often stored as 1_01d_01.bin inside a ZIP archive).

| Symptom | Cause | Repack Fix | |---------|-------|-------------| | Naomi 2 boots to "ERROR 31" | IC501 region mismatch | Set MD0=1, MD1=0 in repack config | | DIMM board not recognized | Security handshake timeout | Increase repack handshake delay from 50ms to 200ms | | Graphical glitches after 5 mins | Table diffusion insufficient | Use SHA-256 instead of XOR for scrambling | demul mpr 21931 ic501 repack

To understand the "repack" solution, we must decode each component of the error: mpr-21931

If you mean repacking the ROM set for DEMUL so it bypasses IC501 checks: In the emulation scene, "repack" has two meanings:

Whether you find a ready-made repack or build your own from MAME sources, remember: emulation is as much about understanding the hardware as it is about playing the games. Treat your ic501 with care—back it up, verify its checksums, and one day you might be the one repacking it for the next generation of retro gamers.

In the emulation scene, "repack" has two meanings:

If your repack lacks a checksum file, cross-reference with MAME’s naomi.xml or demul.sfv .