Analogue-sequencer

> I've just upgraded my DIY P3 to version 1.006  it was working well
> till yesterday. the problem is that the lcd lights up but the P3
> doesn't boot and nothing appears on the screen.
> 
> I suspect that the cpu is dead. 
> Could someone help me? I can't understand where's the bug.

There is a very small chance that the CPU can corrupt its flash contents.
This has happened to a couple of the new type CPUs, and a few of the older
CPUs too.
It's not a significant number, but that doesn't make it any less annoying if
it happens to yours.
It certainly should not do this - the device has a power management
controller on board, that forces it into reset as soon as the Vcc line goes
out of spec, and the bootloader code itself is so simple there really isn't
any chance it can be a bug there.

If you do find your P3 CPU fails to boot after running without problems,
just let me know and I'll send you a new CPU to swap for the one with
amnesia.
A re-flash with the serial bootloader has fixed all rogue CPUs, so it's not
a permanent failure - but you can't do it yourself.

I'll be trying out a different manufacturers CPU, and will switch to that if
it works out, rather than take the chance Atmel have some weird chip bug
going on.

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