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Dump flash memory

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2PAC Mafia

Member
Hello everybody,

sometimes I get a very expensive yacht display (around 8.000€) which fails at the processor board. It has mainly 3 modules and the processor board where is an embedded system Windows based with all the specific software is failing. After trying to repair some of them going into the hardware of this board I couldn´t finish it and I have suspected the problem comes from a corruption at flash memories.

Now, my question is if you know some company who works dumping these types of memories, there are SMD memories model and BGA memories model. Both types of boards have connector probably to communicate with processor probably by SPI or I2C bus.

Of course, get this processor board is not possible through the manufacturer, you have to buy a complete new display. During this year I have faced with 4 or 5 of them and I now in the future I´ll get the same problem.
 

alec_t

Well-Known Member
Most Helpful Member
Do you have access to a known non-corrupt memory of identical type to the corrupted one?
 

2PAC Mafia

Member
Not now, I have some damaged ones, but always there are two of these units installed on board. May be first step would be do tests with a partially damaged one, which may be has problems at boot sector.
 

alec_t

Well-Known Member
Most Helpful Member
If you only have corrupted/damaged files, how will you know what the correct file contents should be?
 

schmitt trigger

Well-Known Member
Even then, the perfectly good values of non-corrupt memory table may be different from another unit's perfectly good values.

The products we manufacture all use flash memory to store the calibration constants. Of all the memories which I've dumped over the years, no two are alike, ever.

The way we know a memory has been corrupted, is to read the stored CRC and then perform a CRC on the actual memory's contents.
If they differ, then we have a corrupted table.

Some of our newer products actually store the calibration table twice, and perform a CRC on each.
Upon startup, the processor calculates the CRC from the primary table to determine if there is a corruption. If so, then the backup table is employed.
 

2PAC Mafia

Member
I mean, I want to know if somebody can copy a good flash content, then remove flash from bad Display and put a new programmed one.

May be there is a way to do it by ICP or by removing memories, I don't know if is possible to do that in BGA format.

Before doing that on a good Display may be there is the possibility to work on a bad one just to know which problems you can find or possibilities about reading access, may be it's not possible because it's protected and we have to forget about repairing it.
 

2PAC Mafia

Member
Even then, the perfectly good values of non-corrupt memory table may be different from another unit's perfectly good values.

The products we manufacture all use flash memory to store the calibration constants. Of all the memories which I've dumped over the years, no two are alike, ever.

The way we know a memory has been corrupted, is to read the stored CRC and then perform a CRC on the actual memory's contents.
If they differ, then we have a corrupted table.

Some of our newer products actually store the calibration table twice, and perform a CRC on each.
Upon startup, the processor calculates the CRC from the primary table to determine if there is a corruption. If so, then the backup table is employed.
Then you mean after copying a good memory and put a new memory with those data programmed may be is not working on the other display?
 

schmitt trigger

Well-Known Member
If the stored values are indeed calibration coefficients, that is correct, it may not work properly.

Think about it this way: If all calibration values were always absolutely identical, there would be NO need to calibrate something, wouldn't it?

However, if they are only storing other parameters, then your idea could work.

But first things first, what type of flash memory it uses?
 

2PAC Mafia

Member
I have these types depending on model of display:

SMD: DA28F640J5A-150
BGA: 29F128J3A

At both boards there are 2 flashes.
 

2PAC Mafia

Member
The processors are:

SMD: Intel Strong ARM SA-1100 S0005 JD6724LB
BGA: Intel Strong ARM GDS-1110BD L3190504

my question is, if I replace the processor, has it some internal data stored or does it take the data from the flash? That´s also one test I would like to do, replace the processor.
 

Tony Stewart

Well-Known Member
Most Helpful Member
I would use Huntron Tracker method with 100k series R from a sig. gen. to measure VI response in XY mode and compare pins for open BGA solder joints.
 
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