USS Protocol

[adohm]

I have a customer who uses a proprietary controller with their Atlas Copco air compressor, and a Siemens SimoVERT Masterdrive. The drive blew up and the customer wants to replace it with an ABB drive. So far my largest stopping point is the communications. The Siemens drive uses a USS protocol for communications through an RS485. There are no modules available for ABB that I can find that enable this sort of communication. Even if there was, because the controller is proprietary, I don't know what addresses, functions, etc that it's sending\recieving. I've tried calling Atlas Copco for help but they haven't returned my calls. I know this isn't PLC related directly, but these forums have been a great source of information for a long time and I hope to get some sort of answers from here. Is it possible? How? Thanks!