Serial Port 1 And 2 Rs232/Rs485 Interfaces; Table 2-2 Rs-232 Signals On J3 And J4 Serial Ports; Table 2-3 Rs-422 4-Wire Signals On Serial Ports (J3 Only); Table 2-4 Rs-485 2-Wire Signals On Serial Ports(J3 Only) - Lantronix xPico User Manual

Serial Port 1 and 2 RS232/RS485 Interfaces

The evaluation board has one multiprotocol RS-232/RS422/RS485 port and one RS232 port
for connection to the xPico internal UARTs. The ports are DB9 type connectors labeled J3
and J4. Included with the kit is a DB9-to-DB9 null modem cable (Lantronix P/N 500-164-R).
The null modem cable can be used to connect either J3 or J4 directly to a standard PC
RS232 serial port.
The tables below list the RS232/RS422/RS485 signals and corresponding pins on the
evaluation board DB9 connectors. All signals at J3 are level-shifted by a multiprotocol
transceiver. J4 is an RS232 port only.
The J3 DB9 port is configured for RS232, RS422 (4-wire), or RS485 (2-wire) by jumper
settings on JP11 and JP12.
xPico Development Kit User Guide
Table 2-2 RS-232 Signals on J3 and J4 Serial Ports
xPico Evaluation Board
PIN FUNCTION
Serial Port
TX_232 (Data Out)
RX_232 (Data In)
CTS_232 (HW Flow Control Input)
RTS_232 (HW Flow Control Output)
DTR_232 (Modem Control Output)
GND (Ground)
Table 2-3 RS-422 4-Wire Signals on Serial Ports (J3 only)
xPico Evaluation Board
PIN FUNCTION
Serial Port
TX- (Data Out)
RX+ (Data In)
TX+ (Data Out)
RX- (Data In)
GND (Ground)
Table 2-4 RS-485 2-Wire Signals on Serial Ports(J3 only)
xPico Evaluation Board
PIN FUNCTION
Serial Port
TX-/RX- (Data IO)
TX+/RX+ (Data IO)
GND (Ground)
Table 2-5
DB9
Pin #
DB9
Pin #
3
2
7
4
5
DB9
Pin #
3
7
5
lists the correct jumper installation for each mode.
2: Development Kit
3
2
8
7
4
5
9