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I will try explain how it works on example
This method works if we know what layout to use
For this case layout is AU6998 1096 Xor 6771_256
1096 is two sectors by 512 bytes protected by 72 ECC bytes
6771 is Xor type. 256 pages is xor block
All pages in block have same bad bytes positions
But even and odd blocks have different bad bytes positions
So we will need do our work two times. First for even blocks, and after for odd blocks
I think in most cases Xor block will be same with bad bytes block. But can be different
In different dumps bad bytes positions will be different
First add "Cut Bad Bytes" step in mix editor. And select it
Open Bad Bytes Editor
Set in Properties menu Block Size in Pages = 256 and set Enable = on
Open Hex Editor that show sectors after layout is applied
Find place with zeros
Usulay i jump with Block Size from start of dump until i find it (ctrl + page_down)
Check hot keys here: Hex Editor
Or use search function. For example, 00000000/h/0x400000/0
This sector have only zeros in data
But because of one extra byte added at position 0x88, Xor pattern is shifted and data is not unxored. You see it as random bytes
You can see that ECC = Error
We will see ECC = OK, when we remove all bad bytes from sectors protected by ECC (2 x 512)
Page Size is 17664. So, there is 16 pairs of (512x2 + ECC) sectors in one page
At right side of screen you can see raw page
Green bytes is data. Blue bytes is SA (ECC)
Select first wrong byte at left side of screen
It will be automaticaly selected at right side of screen
You can see that there is two bytes with same value
I see two different ways how controller fill bad byte
Some controllers fill it with same value as in our case
Some controllers fill it with FF
You can check that at all pages in block this two bytes have same values
To do it jump with Page size at left side of screen (ctrl + page_down)
Page Size is 17664 = 0x4500, so need set Jump Size = 0x4000
Double click on selected bad byte
You can see that at left side of screen we have more zeros now
And now we have byte byte at position 0x8d
Double click on it to remove
With this method we can clean our two sectors (512 x 2)
If we are lucky and there is no bad bytes in ECC, ECC will be green
0x308000000 (first)
0x308000200 (second)
0x308000400 (first of next pair)
And at first sector of next pair, you will see zeros at start of sector
If we are not lucky, ECC will be Error, and no zeros at next pair,
need search for bytes with same values at ECC area under data area
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