Communication interface method

摘要

A communication interface responds to a communication protocol for interfacing a controller and any of a plurality of discrete I/O devices. Each discrete I/O device has a different configuration. The interface has a plurality of modes of operation to accommodate the discrete I/O devices. In a first mode of operation, the interface accommodates a first discrete I/O device wherein a plurality of input pins input signals from a particular discrete I/O and a plurality of output pins output signals to the particular discrete I/O device. In a second mode of operation, the interface accommodates a second discrete I/O device wherein the input pins form a bidirectional input/output port and the output pins form a control and address line for controlling the second discrete I/O device and other discrete I/O devices.