The Programmable Coprocessor Module (PCM) is a Coprocessor to the PLC CPU. It can be programmed to perform operator interface, real time computations, data storage, data acquisition and data communications functions. It communicates with the PLC CPU over the backplane and can access user and system data using extensions to the powerful MegaBasic language. No application program support is required in the PLC CPU. Many PCMs can be supported in a single IC697 PLC system and each can accommodate an optional expansion memory up to 512 Kbytes.Dual tasking allows running a MegaBasic program at the same time the PCM is used as a communications interface. Operation of the module may be initialized by a pushbutton or by an attached PCM development system. The status of the PCM is indicated by three green LEDs on the front of the module.