What is RPI(TM)?
Rockwell Protocol Interface (RPI(TM)) is a technology that allows error correction and data compression (ECC) technologies to be performed in the PC host computer, rather than in the modem hardware, as has been done traditionally. Technically speaking, RPI is an asynchronous HDLC (High Level Data Link Control) link that operates between a PC and a modem, allowing data compression and error correction to take place on the host PC. This allows RPI to operate using standard PC COM ports, or standard serial cards. The V.42bis bit stream presented to the remote modem from an RPI modem looks exactly like that which would come out of a traditional hardware implementation of V.42bis, fully synchronous and full duplex. MNP levels 2,3,4,5 are supported as well as V.42 LAP-M, and V.42bis. To get ECC with RPI, as one would get using a hardware implementation of ECC, the PC comm application needs either a driver or a software package that supports RPI; the modem itself needs firmware that supports
