I ran out of serial ports again and put an old PCI to 2 serial port adapter in. While setting up the port config, I noticed it had RS485 settings. Did I waste $110 in purchasing an RCS 8 port RS232 - RS485 adapter for my TR40 serial thermostat? The serial adapter could not have been more than $25 from memory. 8 ports is overkill for me right now. No real regrets, just interested if this could have been a solution. Any thoughts?