11-01-2021, 04:17 PM
I recently flashed a custom BIOS for my HP 6730B provided by Maxinator, however this BIOS bricked my laptop so now I need help restoring it.
I initially tried creating a USB recovery drive but the laptop would not initialize BIOS recovery.
Next I tried using the Win+B and Win+V commands, but neither brought up the BIOS recovery utility.
Next I decided to see what I could do with my CH341A, so I disassembled the laptop and hooked up the chip to a separate laptop. Upon reading the chip with ASProgrammer, I was able to confirm that the custom BIOS provided to me was flashed correctly.
I next tried to wipe and flash the EEPROM with the original BIOS, however it appears that the EEPROM is stuck in Write Disable Mode, so although I was able to erase the custom BIOS, I cannot reflash the original BIOS. Using "Unprotect" in ASProgrammer does not unprotect the chip. Checking the status registers for my EEPROM (SST25VF016B) confirms that WREN (Write Enable) is low (0) and writing is disabled.
According to the datasheet (attached to my post) for this EEPROM, Writing can be enabled by sending the hex code 06 to the IC, however it's not described how to send this code in the datasheet. Does anyone know how to re-enable write mode on this EEPROM? Any help is greatly appreciated!
I initially tried creating a USB recovery drive but the laptop would not initialize BIOS recovery.
Next I tried using the Win+B and Win+V commands, but neither brought up the BIOS recovery utility.
Next I decided to see what I could do with my CH341A, so I disassembled the laptop and hooked up the chip to a separate laptop. Upon reading the chip with ASProgrammer, I was able to confirm that the custom BIOS provided to me was flashed correctly.
I next tried to wipe and flash the EEPROM with the original BIOS, however it appears that the EEPROM is stuck in Write Disable Mode, so although I was able to erase the custom BIOS, I cannot reflash the original BIOS. Using "Unprotect" in ASProgrammer does not unprotect the chip. Checking the status registers for my EEPROM (SST25VF016B) confirms that WREN (Write Enable) is low (0) and writing is disabled.
According to the datasheet (attached to my post) for this EEPROM, Writing can be enabled by sending the hex code 06 to the IC, however it's not described how to send this code in the datasheet. Does anyone know how to re-enable write mode on this EEPROM? Any help is greatly appreciated!