Analogue-sequencer

HI ,this evening,when i switch on my P3 "chk FAIL 2BBB" appears...i
choice" boot" and it works...but at each switch on the same
message...this happens after a bug on my midi interface edirol um
880..i ve planed to upgrade tomorrow with memory exp and version
4..informations please...thanks Colin, for the two memory expansions
i' ve received for Christmas...best regards

> HI ,this evening,when i switch on my P3 "chk FAIL 2BBB" appears...i
> choice" boot" and it works...but at each switch on the same
> message...

This means that the checksum stored in the boot block does not match the
checksum calculated for the contents on the flash memory.
The fix is to re-load the OS via sysex.
If you don't do something that causes the damaged part of the OS to execute,
it will work as normal, but there may be a surprise waiting for you
somewhere...

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

--- In analogue-sequencer@yahoogroups.com, "Colin Fraser" <colin@...>
wrote:
>
>  Thanks,that's i've done..with a wiping all data..brand new
banks..tomorrow version 4 !!!long long pattern...when you talk about
"surprise"do you think the chip is damaged?
                  Best regards


> > HI ,this evening,when i switch on my P3 "chk FAIL 2BBB" appears...i
> > choice" boot" and it works...but at each switch on the same
> > message...
> 
> This means that the checksum stored in the boot block does not match the
> checksum calculated for the contents on the flash memory.
> The fix is to re-load the OS via sysex.
> If you don't do something that causes the damaged part of the OS to
execute,

> it will work as normal, but there may be a surprise waiting for you
> somewhere...
> 
> Best regards,
> Colin Fraser
> Sequentix Music Systems Ltd
> http://www.sequentix.com
>

All data were lost,before reloading the OS ;-(...place for news
patterns..that's life.



 In analogue-sequencer@yahoogroups.com, josh <notjoshua@...> wrote:
>
> so reloading the OS should leave all data intact?
> Thanks Collin!
> 
> On Sun, Jan 18, 2009 at 4:36 PM, Colin Fraser <colin@...> wrote:
> 
> >
> > > HI ,this evening,when i switch on my P3 "chk FAIL 2BBB" appears...i
> > > choice" boot" and it works...but at each switch on the same
> > > message...
> >
> > This means that the checksum stored in the boot block does not
match the

> > checksum calculated for the contents on the flash memory.
> > The fix is to re-load the OS via sysex.
> > If you don't do something that causes the damaged part of the OS to
> > execute,
> > it will work as normal, but there may be a surprise waiting for you
> > somewhere...
> >
> > Best regards,
> > Colin Fraser
> > Sequentix Music Systems Ltd
> > http://www.sequentix.com
> >
> >  
> >
> 
> 
> [Non-text portions of this message have been removed]
>

> so reloading the OS should leave all data intact?

The pattern data is held in battery backed RAM.
As long as a corrupt OS doesn't over-write any of the data there, it should
be fine once the OS is re-loaded.
The checksum for the OS would come up wrong even if just a single bit in the
whole OS was wrong.
But no problem would occur with the OS unless the section of code with the
bad bit were to execute, and the bad bit cause a change in the code that
made it do something bad.

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

> 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

so reloading the OS should leave all data intact?
Thanks Collin!

On Sun, Jan 18, 2009 at 4:36 PM, Colin Fraser <colin@sequentix.com> wrote:

>
> > HI ,this evening,when i switch on my P3 "chk FAIL 2BBB" appears...i
> > choice" boot" and it works...but at each switch on the same
> > message...
>
> This means that the checksum stored in the boot block does not match the
> checksum calculated for the contents on the flash memory.
> The fix is to re-load the OS via sysex.
> If you don't do something that causes the damaged part of the OS to
> execute,
> it will work as normal, but there may be a surprise waiting for you
> somewhere...
>
> Best regards,
> Colin Fraser
> Sequentix Music Systems Ltd
> http://www.sequentix.com
>
>  
>


[Non-text portions of this message have been removed]

-thanks ...COLIN,the famous cheksum..i've melt in the jd 990 roland
..for edit a template with an external surface control(novation sl
25)..i 've broken my head with...;-)it's more easy to drink a bad 
french wine(i'm french)...Best regards ..

-- In analogue-sequencer@yahoogroups.com, "Colin Fraser" <colin@...>
wrote:
>
>  
> > 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
>