David,
The steps to recover the installer code have been provided on this site. You should be able to just send the proper eeprom chip to someone with an eprom burner to recover the code. That should be easier to ship one chip then disconnect and ship the whole panel.
The following was posted by
@Airdorn:
"If you have access to an EPROM programmer then finding the installer's code is very straightforward and easy. The Omni Pro II uses a 28c256 256k EEPROM that, as we all know, has no facility for encryption. All system data stored bitwise is in clearview.
Power down the system and pull the 28c256 EEPROM. it is the only socketed chip on the board. Place it in your EPROM programmer and read it.
Address 0x2859 contains the first 2 digits and address 0x285A contains the last 2 digits of the installer code.
After gleaning this information, reinstall the EEPROM and power the system back up.
WARNING: DO not attempt to change the contents of the EEPROM using your programmer. If the system data is checksummed then the Omni PRO II might simply crash, factory default, or some other undesirable behavior. Always use the system itself to make any changes to the chip data.
My programmer is USB running Windows software, model GQ-4x4 sold by mcumall.com. I use it a lot in my old arcade game hobby but I've also used it for discovering codes on alarm panels like the Interlogix Concord 4 and this one."