RTW Porta Monitor Wiederbelebung

[sensor]

Hey guys I own two Portamonitors, one is 1064 and the other is 1063-PLUS. I had problems with both the NEC TFTs and what solved the issues was a total recap of the driver and inverter boards. Now I'm trying to reverse engineer the onboard firmware to enable the RTA option on the 1063. I've dumped both EEPROMs but they are identical. The only thing that it's stored on those chips is the ASCII characters for the menus... I've looked around the board and can't figure out on what chip is the serial number is stored. I'm thinking on changing to the same on as my 1064 and apply the code (which I fortunately have). Any ideas?
Under the two heatsinks there are 2 ICs from Motorola XCF56009FJ81 https://www.kynix.com/Detail/597287/XCF56009FJ81.html the datasheets states that it can support up to 512KB flash memory...

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