Sun Microsystems 60 Serial Port a and B RS-423/RS-232 Connectors, Used by the data terminal

B.1.2 Serial Port A and B (RS-423/RS-232) Connectors

The serial port A and B connectors are DB-25 type connectors located on the motherboard back panel. FIGURE B-2illustrates the serial port A and serial port B connector configuration and TABLE B-2lists the connector pin assignments.

13	1	Serial port B
25	14
13	1	Serial port A
25	14

FIGURE B-2Serial Port A and B Connector Pin Configuration

TABLE B-2Serial Port A and B Connector Pin Assignments

Pin	Mnemonic	Signal Name	Description
1		Not connected	None
2	TXD	Transmit Data	Used by the data terminal
			equipment (DTE) to transmit data
			to the data circuit equipment (DCE).
			Except when control data is being
			sent, RTS, CTS, and DCD must be
			ON for this line to be active.
3	RXD	Receive Data	Used by the DCE in response to
			received data from the DTE.
4	RTS	Ready To Send	Used by the DTE to condition the
			DCE for data transmission. The
			transition to ON directs the DCE to

go into transmit mode. The transition to OFF directs the DCE to complete the transmission.

Appendix B Signal Descriptions B-3