Analogue-sequencer

> when you talk about
> "surprise"do you think the chip is damaged?

No, by a "surprise", I mean you may get unexpected behaviour in the OS, such
as a crash or other weirdness.

The most likely way to get a checksum error on the P3 would be to do an
incomplete firmware update.
The firmware is loaded in blocks of 128 bytes. Each block is written to the
flash memory in the CPU as it is received as a sysex block.
At the end of the sysex file is a checksum.
The checksum is stored in the boot block, and compared with a checksum
calculated from the flash on every boot.
If the boot block checksum doesn't match the generated checksum, the boot
loader shows the error message.

If you were to do half an OS update and then stop, some of the flash would
be over-written, but not all, so the checksum would be wrong.
This would be an unsafe OS, as it would be the first part of one build on
top of the latter part of another.

If you get a checksum error without having recently updated the firmware,
then it is most likely just a spurious error that has occured in a single
byte of flash. Continued booting of the OS may work with no problem, but a
re-flash via sysex would be strongly recommended.

Best regards,
Colin Fraser
Sequentix Music Systems Ltd
http://www.sequentix.com