About the Serial Ports

The system provides two serial communication ports through a pair of DB-25 connectors located on the rear panel. Both ports are capable of synchronous and asynchronous communication. In synchronous mode, each port operates at any rate from 50 Kbaud to 256 Kbaud when the clock is generated internally. When the clock is generated from an external source, synchronous communication occurs at rates up to 384 Kbaud. In asynchronous mode, either port supports baud rates of 50, 75, 110, 200, 300, 600, 1200, 1800, 2400, 4800, 9600, 19200, 38400, 57600, 76800, 115200, 153600, 230400, 307200, and 460800 baud.

Both serial ports can be configured to provide EIA-423 or EIA-232D signal levels. Signal levels are controlled by jumpers located on the system's main logic board. The default setting is EIA-423. For more information about configuring the serial port jumpers, see "About Serial Port Jumpers".

See "Reference for the Serial Port A and B Connectors" for the connector diagram, rear panel icon, and pin assignments.