[sdiy] MIDI Sys Ex packet length

[Richie Burnett]

If doing a flash update of firmware over conventional MIDI via System 
Exclusive is it wise to break the download into many smaller packets of say 
128 or 256 bytes in length?

I was planning on using MIDI-Ox for Sys Ex flash updates, but I guess I 
could also incorporate the Sys Ex packets into a standard MIDI file that 
could be played back on any capable hardware?

Does anyone know if MIDI-Ox has any provision for resending packets if 
something like a CRC fails, or would I have to write my own program at the 
PC/Mac end to check for ack/nack and resend the necessary corrupted packets?

I've already discovered that certain cheap Chinese USB to MIDI interfaces 
don't correctly handle MIDI messages containing more than 3 bytes!!! So 
they're a non-starter from the outset.

-Richie,