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RT-AC86U 1024MB RAM support.

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OK, back to my situation. The reason i want to build CFE was due to this NAND problem
The "bad" one has already replaced a new nand chip. (the full log is in attachment)

My good rt-ac86u
Rich (BB code):
nand: Could not find valid ONFI parameter page; aborting
nand: device found, Manufacturer ID: 0xc2, Chip ID: 0xda
nand: Macronix NAND 256MiB 3,3V 8-bit
nand: 256 MiB, SLC, erase size: 128 KiB, page size: 2048, OOB size: 64
bcm63xx_nand ff801800.nand: Adjust timing_1 to 0x65324458 timing_2 to 0x80040e54
bcm63xx_nand ff801800.nand: detected 256MiB total, 128KiB blocks, 2KiB pages, 16B OOB, 8-bit, BCH-4

My Bad rt-ac86u
Rich (BB code):
NAND ECC BCH-8, page size 0x800 bytes, spare size used 108 bytes
NAND flash device: , id 0xc2da block 128KB size 262144KB
...
nand: device found, Manufacturer ID: 0xc2, Chip ID: 0xda
nand: Macronix NAND 256MiB 3,3V 8-bit
nand: 256 MiB, SLC, erase size: 128 KiB, page size: 2048, OOB size: 64
bcm63xx_nand ff801800.nand: Adjust timing_1 to 0x65324458 timing_2 to 0x80040e54
bcm63xx_nand ff801800.nand: detected 256MiB total, 128KiB blocks, 2KiB pages, 27B OOB, 8-bit, BCH-8
 

Attachments

  • bad_bootloop.txt
    26.9 KB · Views: 104
Last edited:
if you need i have working full nand dump
Although i already have two full nand dump by my own with two different tools from a good rt-ac86u.
(one was a python script using dn command to dump content from cfe mode. Another was a nand programmer)
But, yes. I'd be glad if you can share it (Prefer google driver or Mega.nz, or i can provide a private FTP). Maybe i can find something difference.
 
if you need i have working full nand dump
With your full nand dump, I got the same "bad result" as mine before. :p
(I use a new nand chip with 0 bad block.)

Rich (BB code):
NAND ECC BCH-8, page size 0x800 bytes, spare size used 108 bytes
NAND flash device: , id 0xc2da block 128KB size 262144KB
...
nand: device found, Manufacturer ID: 0xc2, Chip ID: 0xda
nand: Macronix NAND 256MiB 3,3V 8-bit
nand: 256 MiB, SLC, erase size: 128 KiB, page size: 2048, OOB size: 64
bcm63xx_nand ff801800.nand: Adjust timing_1 to 0x65324458 timing_2 to 0x80040e54
bcm63xx_nand ff801800.nand: detected 256MiB total, 128KiB blocks, 2KiB pages, 27B OOB, 8-bit, BCH-8

And your full nand dump includes OOB block (spare area).
So, i tried two method with the dump file.

Method 1: (program the nand with spare area [oob])
1. Erase the nand.
2. Program the nand with full dump (276824064 Bytes, 264MB)
3. Dumpping the nand and compare to the source file. Confirmd they are the same.
4. boot with the nand chip
5. bad result

Method 2: (program the nand without spare area [oob] )
0. Dumpping the nand from Method 1 but does not include OOB.
1. Erase the nand chip
2. Program the nand with the dump from Step 0 (268435456 Bytes, 256MB)
4. Dumpping the nand again, and compare to the Step 0. Confirmd they are the same.
5. boot with the nand chip
6. bad result.

Attached photo is my nand programmer (NANDO), and my modification with rt-ac86u (for easy change nand chip)
 

Attachments

  • Screenshot from 2021-12-09 15-24-47.png
    Screenshot from 2021-12-09 15-24-47.png
    39.9 KB · Views: 144
  • S__12419076 (大).jpg
    S__12419076 (大).jpg
    98.3 KB · Views: 155
Last edited:
what error does the router show?
With my dump asus used BCH-8 algorithm ?

Yes, my dump has spare area.

i used Rose's metal for fast solder-desolder NAND. it has a melting point of 100C and can be easily soldered with a dryer for soldering

Code:
NAND ECC BCH-4, page size 0x800 bytes, spare size used 64 bytes
NAND flash device: , id 0xc2da block 128KB size 262144KB

Code:
nand: device found, Manufacturer ID: 0xc2, Chip ID: 0xda
nand: Macronix NAND 256MiB 3,3V 8-bit
nand: 256 MiB, SLC, erase size: 128 KiB, page size: 2048, OOB size: 64
bcm63xx_nand ff801800.nand: Adjust timing_1 to 0x65324458 timing_2 to 0x80040e54
bcm63xx_nand ff801800.nand: detected 256MiB total, 128KiB blocks, 2KiB pages, 16B OOB, 8-bit, BCH-4

 

Attachments

  • asus-uart.txt
    50.1 KB · Views: 120
Last edited:
what error does the router show?
With my dump asus used BCH-8 algorithm ?

Yes, my dump has spare area.

i used Rose's metal for fast solder-desolder NAND. it has a melting point of 100C and can be easily soldered with a dryer for soldering
A good suggestion of using Rose's metal.
But, as i had modified my router to an online nand programmer and i also have another offline nand programmer.
It let me easily change / switch nand chip live, without worried about the soldering or desoldering.

OK, back to my issue XD. I think the ECC problem was the miss configuration of my usb-to-uart converter.

1639536217244.png
1639536264425.png


When i use USB - to - TTL mode, and connect the TX/RX/GND from convert board to AC86U board,
Then boot up the router, i got following abnormal bootstrap register and nand config

Rich (BB code):
Boot Strap Register:  0x6fc43
NAND->NandAccControl = 0xc308001b
08 -> ECC bits => BCH-8
1b -> OOB arg => 108 bytes OOB

But if i use USB - to - 232 mode, and connect the TX/RX/GND from convert board to AC86U board,
Then boot up the router, i got following correct bootstrap register and nand config

Rich (BB code):
Boot Strap Register:  0x6fc42
NAND->NandAccControl = 0xc3040010
04 -> ECC bits => BCH-4
10 -> OOB arg => 64 bytes OOB

Boot up router with usb converter ==>TTL mode
TX/RX/GND connected
TTL mode
no pin connected
RS232 mode
TX/RX/GND connected
Boot Strap Register0x6fc430x6fc420x6fc42
ECC bitsBCH-8BCH-4BCH-4
OOB size (spare area)108 Bytes64 Bytes64 Bytes

Although the correct config of my usb converter solved the ECC error problem.
But i still can not boot up with a good nand which flashed with official asus firmware (version: 2021/11/25 -- 3.0.0.4.386.45956 // FW_RT_AC86U_300438645956.w)
Maybe is a hardware issue......
Logs attached => 86u.log

i'll try with other nand chip tonight. (i bought about 10pcs)
 

Attachments

  • 86u.txt
    39.2 KB · Views: 110
Last edited:
Hi,
do I need to modify CFE and firmware to change to 1G memory?
Where is the source code of memory config 0x1427 in CFE?
 
After I replaced the memory, the Lan4 light turned on when I turned it on.
Did I solder the memory wrong? or need TTL to replace the file
 
After I replaced the memory, the Lan4 light turned on when I turned it on.
Did I solder the memory wrong? or need TTL to replace the file
After replacing the memory, the router should work as usual. should show 512 MB. after editing the firmware will show 1 GB
 
After replacing the memory, the router should work as usual. should show 512 MB. after editing the firmware will show 1 GB
Well, the model I soldered is MT41K512M16HA-125:A, I think I need to re-solder it again, or change to the same memory model as yours
 

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