The communication is strictly serial. The chip that I would be communicating with is embedded inside a finished product. The communication is used to calibrate the device prior to shipment. The customer is currently using a PC-based control and a National Instruments USB-to-I2C converter. It works, but it's a band-aid system. They want to upgrade to something that can better handle the industrial environment and is easier to troubleshoot. If necessary, I can use the PLC for setting the calibration conditions, then a mini-PC to handle the communcation between the PLC and the finished product. I'd rather not as it adds another layer to the system, but I can if that's my best bet.