pcbbc
26th September, 2018, 06:02 PM
I have a problem... I have flashed a bad firmware onto a 192 RNS-E. Unfortunately the checksums are all good, just some of the code I patched is invalid and is causing the unit to constantly reboot every second or so.
I'm looking for a way to get into the emergency firmware recovery/bootloader mode. The one with the Japanese writing on the screen where you can insert a good firmware on CD and it will re-flash the unit back to a known good state.
Is their a jumper link on the board to force this behaviour on start-up? Even with good firmware checksums?
If not, I am thinking to "corrupt" IC6 somehow so it looks like a bad/partial flash. Then the recovery mode will start, instead of the corrupt OS code I foolishly programmed. The BIOS and the bootloader are in the first 64K of that block, so if I remove an address line - say A14 - and tie to ground, then every other 64K block should be mapped to the previous 64K of flash. The boot loader will think the other module checksums are bad, and go to recovery mode?
Is there an easier or less risky way, short of phyiscally removing the IC6 and re-flashing?
I'm looking for a way to get into the emergency firmware recovery/bootloader mode. The one with the Japanese writing on the screen where you can insert a good firmware on CD and it will re-flash the unit back to a known good state.
Is their a jumper link on the board to force this behaviour on start-up? Even with good firmware checksums?
If not, I am thinking to "corrupt" IC6 somehow so it looks like a bad/partial flash. Then the recovery mode will start, instead of the corrupt OS code I foolishly programmed. The BIOS and the bootloader are in the first 64K of that block, so if I remove an address line - say A14 - and tie to ground, then every other 64K block should be mapped to the previous 64K of flash. The boot loader will think the other module checksums are bad, and go to recovery mode?
Is there an easier or less risky way, short of phyiscally removing the IC6 and re-flashing?