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HEEEELP! CHK FAIL = 7D5C

2009-10-05 by atuzzi

Hello Friends,

Hello Colin,

I have one of the first models, with case in black (style Paul Nagle).
there is an inner xformer (220 -> 7AC).

yesterday I had some problem on the power line and suddenly the P3 shut down.
TOTAL PANIC!!!

I think the problem is the inner xformer
anyway I have a voltage controlled bank power and I gave directly 5volts to the boards

and at the startup I'm getting "chk fail = 7d5c" and p3 stops

Aiutoooooo!!! (heeellllp!!)

What I can do ? what are the correct steps to debug the problem?

thank you
Antonio

Re: HEEEELP! CHK FAIL = 7D5C

2009-10-05 by atuzzi

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:

Show quoted textHide quoted text

>
>  
> > 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
>

RE: [analogue-sequencer] HEEEELP! CHK FAIL = 7D5C

2009-10-05 by Colin Fraser

> 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

Re: HEEEELP! CHK FAIL = 7D5C

2009-10-28 by atuzzi

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:

Show quoted textHide quoted text

>
> 
> 
> 
> 
> 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
> >
>

Analogue-sequencer

HEEEELP! CHK FAIL = 7D5C

HEEEELP! CHK FAIL = 7D5C

Re: HEEEELP! CHK FAIL = 7D5C

RE: [analogue-sequencer] HEEEELP! CHK FAIL = 7D5C

Re: HEEEELP! CHK FAIL = 7D5C

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