PAC Systems* RX3i Serial Communications modules expand the serial Communications capabilities of the RX3i system. Serial Communications module IC695C mm002 provides two independent, isolated serial ports. Serial Communications module IC695C mm004, illustrated at right, provides four independent, isolated serial ports. Up to six Serial Communications modules can be located in the main PAC Systems RX3i backplane. The IC695C mm00xCA modules are the conformal coated versions of the IC695C mm00x modules. The IC695C mm004LT version is for low temperature applications (-40C). Each port can be configured for MODBUS Master, MODBUS Slave, CCM Slave, DNP3 Master, DNP3 Slave, or Serial I/O protocol. If any port is configured for DNP3 Master or Slave, the other ports on the module can only be configured for DNP3 Master or Slave. For modules with firmware version 1.32 or later, half-duplex flow control can be configured using Machine Edition Release 5.90, SP1, SIM 6 or later. Otherwise, flow control defaults to full-duplex.