Trouble Programming Flash on MC9S12A128 – “Device or region is not blank or failed erase”

[Nico_V]

Hi all,
I have a PCB with a Freescale MC9S12A128 MCU. Unfortunately, the source files are long lost. I’m trying to copy firmware version "4.3" from new old stock to some older stock that currently has firmware "4.0".

Using the above memory dump configuration, on an old board (to avoid bricking a new one), I successfully performed a Verify Flash against the dump and it matched. However, when I tried programming it (after a mass erase), the operation failed with "Device or region is not blank or failed erase"

Any help would be appreciated. Thanks!

[Nico_V · Accepted solution]

Well, it worked... solved! (it wasn't the reset signal)

[Nico_V]

I was able to flash all the contents, except the last two banks of flash: 3E8000 and 3F8000. (I get lost in the redundancy of protection bits and bytes).
Also, the reset signal doesn't change after a Mass Erase