| RS232 / RS485 / RS422<sup>1</sup>
| 6x RJ-11 jacks functioning as RS232<sup>2</sup>,
as half<sup>3</sup>/full-duplex RS485 or RS422 serial ports;
| CAN bus
# The default standard can be configured by jumper E1. See section Serial Ports Configuration.
# FM-SER is classified as DTE (Data Terminal Equipment) in terms of RS232 standard definition.
* Implementation of physical layer (PHY) of RS232 or RS485 serial protocol ports.
* Up to 500kbps data rate from UART to RS232 and up to 15 Mbps data rate to full duplex RS485
* Supports RS422
and half duplex RS485 protocols
* Integrated termination resistors are being switched according to mode of operation.
* Loopback mode for self-testing
=== Configuration ===
'''Serial Ports Configuration'''
Each serial port can be individually configured to act in RS232
mode or RS485 half/full duplex mode. The configuration is selected in fit-PC3 BIOS setup.
The default selection between RS232 and RS485/RS422 is determined by E1 jumper position. Default mode determines the power-up state of the Dual Protocol Transceiver. It is applied to all ports and remains valid in case that software configuration is not performed.
The options of jumper E1 selections are detailed in Table 4.