110502
PRODUCT MANUAL EPX-C380
28
COM1, COM2,
COM3, COM4 Configuration Options in BIOS
1. RS-232 Mode
2. RS-422 Mode with RTS transmitter enable
3. RS-422 Mode with auto transmitter enable
4. RS-485 Mode with RTS transmitter enable
5. RS-485 Mode with RTS transmitter enable and echo back
6. RS-485 Mode with auto transmitter enable
7. RS-485 Mode with auto transmitter enable and echo back
Mode(s)
Configuration Note
2, 4, 5
Require the RTS bit (MCR Bit 1) to be set in order to transmit.
3, 6, 7
Require TX/RX(300) termination on one node.
4
Requires the RTS (MCR Bit 1) be de-asserted in order to receive.
* Each of the RS-422/RS-485 modes allow for jumper selection of transmit and/or receive termination and
biasing resistor(s). An 8-pin configuration jumper is provided for each port.
COM1 =
JP5
COM3 =
JP7*
COM2 =
JP6
COM4 =
JP8*
Termination Resistors
2 4 6 8
□ □ □ □
□ □ □ □
1 3 5 7
RS-422 Termination and Biasing Resistors
TX (100): Places a 100Ω Resistor across the TX+/TX- pair
3-4
RX (100): Places a 100Ω Resistor across the RX+/RX- pair
7-8
TX(300):
Places a 100Ω Resistor from +5V to TX+
1-2
Places a 100Ω Resistor between TX+ and TX-
3-4
Places a 100Ω Resistor from Ground to TX-
5-6
RS-485 Termination and Biasing Resistors
TX (100): Places a 100Ω Resistor across the TX/RX+/TX/RX- pair
3-4
TX/RX(300):
Places a 100Ω Resistor from +5V to TX/RX+
1-2
Places a 100Ω Resistor between TX/RX+ and TX/RX-
3-4
Places a 100Ω Resistor from Ground to TX/RX-
5-6
* COM3 and COM4 are RS-232 only for model EPX-C380-S1-0. RS-422/485 are not supported on
model EPX-C380-S1-0.
Preliminary
