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| Agilent 34461A corrupted flash |
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| analogRF:
there is variable in uboot --- Code: ---erase_env=nand erase 0xC0000 0x40000 --- End code --- i dont know where it is used but shows the env partition must be 256KiB |
| ElectronMan:
--- Quote from: analogRF on July 31, 2023, 12:45:53 am ---I am pretty sure it is not the nand having a physical problem. the pboot is doing a wrong calculation for some reason maybe it is not identifying the correct chip ID --- End quote --- That's a distinct possibility. I read through the datasheet, and it indicates that bad block information is stored on the first page OOB in bytes 0x800-0x801, 0x810-0x811, 0x820-0x821, and 0x830-0x831. Those all appear to be good (they should be 0xFF). Was the PBOOT reflashed at some point, possibly with the wrong one for your flash chip? |
| analogRF:
--- Quote from: ElectronMan on July 31, 2023, 12:56:35 am --- --- Quote from: analogRF on July 31, 2023, 12:45:53 am ---I am pretty sure it is not the nand having a physical problem. the pboot is doing a wrong calculation for some reason maybe it is not identifying the correct chip ID --- End quote --- That's a distinct possibility. I read through the datasheet, and it indicates that bad block information is stored on the first page OOB in bytes 0x800-0x801, 0x810-0x811, 0x820-0x821, and 0x830-0x831. Those all appear to be good (they should be 0xFF). Was the PBOOT reflashed at some point, possibly with the wrong one for your flash chip? --- End quote --- no this meter had not been opened until few days ago also I dumped the pboot from nand and compared the bin file with my good meter and they are identical. |
| ElectronMan:
--- Quote from: analogRF on July 31, 2023, 01:06:52 am --- --- Quote from: ElectronMan on July 31, 2023, 12:56:35 am --- --- Quote from: analogRF on July 31, 2023, 12:45:53 am ---I am pretty sure it is not the nand having a physical problem. the pboot is doing a wrong calculation for some reason maybe it is not identifying the correct chip ID --- End quote --- That's a distinct possibility. I read through the datasheet, and it indicates that bad block information is stored on the first page OOB in bytes 0x800-0x801, 0x810-0x811, 0x820-0x821, and 0x830-0x831. Those all appear to be good (they should be 0xFF). Was the PBOOT reflashed at some point, possibly with the wrong one for your flash chip? --- End quote --- no this meter had not been opened until few days ago also I dumped the pboot from nand and compared the bin file with my good meter and they are identical. --- End quote --- It is starting to get weird now. The flash pages in question look fine. The PBOOT image looks correct. It could be that the chip is not responding properly to parameters and giving the correct ID, but I would expect that to cause problems with UBOOT as well. You could verify that via JTAG by querying the flash chip for parameters. A memory dump might help too. It might still be worth doing an erase on that once-empty block at e0000 and reprogram it to see if anything changes. But other than that, I am out of ideas at the moment. |
| analogRF:
--- Quote from: ElectronMan on July 31, 2023, 01:21:56 am --- It is starting to get weird now. The flash pages in question look fine. The PBOOT image looks correct. It could be that the chip is not responding properly to parameters and giving the correct ID, but I would expect that to cause problems with UBOOT as well. You could verify that via JTAG by querying the flash chip for parameters. A memory dump might help too. It might still be worth doing an erase on that once-empty block at e0000 and reprogram it to see if anything changes. But other than that, I am out of ideas at the moment. --- End quote --- i dont know the JTAG pins on the board. Do you? I will do the erase and re-write but I am pretty sure it will work. maybe the issue is not pboot but it is the uboot I mean if I understand correctly, uboot reads pboot from 0x320000 into memory but it is a packed (gzipped) binary so when the bootm command runs, I suppose it must unpack pboot in order for it to execute and maybe that's where the problem starts |
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