Baslinux mailing list

["Anthony Albert" <albert AT umpi.maine.edu>]

On 9 Dec 2005 at 17:16, sindi keesan wrote:
>>>>>>> QMS finally called back while I was here and explained that the flash 
>>>>>>> rom
>>>>>>> (eeprom?) on the 'controller' (motherboard) is bad ('image checksum
>>>>>>> error') and no, we can't solder in a new one with a soldering iron, 
>>>>>>> but I
>>>>>>> can buy a replacement controller.  They named two wholesalers.
>>>>>>
>>>>>> Ahhhh... this explains much.  Though, I would bet that you could
>>>>>> replace it with a sufficiently skilled touch.  However, you'd probably
>>>>>> need to find another printer of the same model first, from which you
>>>>>> could download the contents of the flash, to program the new one before
>>>>>> soldering it into place.
>>>>>
>>>>> They implied that it could not be soldered by hand. But my partner fixed
>>>>> three dead motherboards by replacing capacitors and two of them still
>>>>> work.  I thought the rom (is this the CMOS?) is usually socketed.
>>>>
>>>> It might be socketed (EPROM & EEPROM often are), but if it's plain ROM
>>>> or flash, then most likely, it's surface-mount soldered, which can be
>>>
>>> They said it was flash rom.  The only two things on the board which don't
>>> appear to be surface soldered are the lithium battery and a VALOR FL1012
>>> which has something to do with ethernet.
>
>Would a dead lithium battery also produce an image checksum error?

I wouldn't think so, but couldn't hurt to ask.  If the battery is low 
enough, then it might be pulling down a supply line far enough to cause 
problems.   I believe I've seen similar behavior in Macintoshes from 
time to time.

>>> What would the flash ROM look like?  These other chips look connected by
>>> metallic spiderweb.
>> [SNIP]
>>
>> Pretty much like any other plastic chip package, unfortunately.  I'd
>> suggest that it's more likely to be one of the larger packages.  You
>> may need to start checking part numbers against Google, if you're
>> serious about replacing it.
>
>Thanks, that is how I identified the ethernet controller chip that is not 
>soldered.  I wonder if QMS would provide software to flash it.
>

Possibly.  A flash image may even be downloadable from their site.  
However, some systems boot entirely from flash, so if the flash fails, 
they are toast...  Good systems boot from ROM, which has just enough 
code to load from flash.
===========================================================
Anthony J. Albert                     albert AT umpi.maine.edu
Systems and Software Support Specialist          Postmaster
Computer Services - University of Maine, Presque Isle
        "This is only temporary, unless it works."
                        --- Red Green