Analogue-sequencer

Hello Friends,

replying to myself:

with Colin help, problems are gone... 
and the P3 is alive and beating again!!

thanks everyone

antonio

--- In analogue-sequencer@yahoogroups.com, "atuzzi" <antoniotuzzi@...> wrote:
>
> 
> 
> 
> 
> nothing...
> I cannot enter in Upgrade Mode (FUNC+PAGE)
> I'm always getting the checksum error (CHK FAIL = 7D5C)
> 
> is the IC marked P3-071 the culprit?
> 
> thanks
> antonio
> 
> --- In analogue-sequencer@yahoogroups.com, "Colin Fraser" <colin@> wrote:
> >
> >  
> > > and at the startup I'm getting "chk fail = 7d5c" and p3 stops
> > 
> > There are two programs in the P3 flash ROM.
> > The bootloader runs at power-on, checks to see if you are holding the keys
> > to trigger firmware update mode, then checks the main program is OK.
> > Then the main program is started.
> > 
> > Chk fail means the bootloader has found the checksum of the main program
> > does not match the stored checksum calculated when the main program was
> > first loaded.
> > You should be able to fix this by re-loading the main program.
> > That is, unless the power spike that seems to have caused corruption in the
> > main program also caused corruption in the bootloader.
> > The bootloader is only a small piece of code, so the chance of it being
> > corrupted if a random byte in ROM is lost is much smaller than for the main
> > program.
> > If the bootloader is damaged, the only fix is to send the CPU back to me for
> > brainwashing.
> > 
> > Best regards,
> > Colin Fraser
> > Sequentix Music Systems Ltd
> > http://www.sequentix.com
> >
>