Flintec FT-112 - RS422 Serial Port

FT-112(D) Panel Weighing Indicator, Technical Manual, Rev.1.0.0, May 2019 Page 23 of 170
4.6.5 RS422 Serial Port
The use of this full duplex serial port and specifications are shown in the Table 4.7 and its pin configuration is
shown in Table 4.8. Refer to page 46 to configure the serial port and page 106 for details on data formats.
Remember 120 ohm line termination resistors should be installed both ends of the RS422 line.
Usage
Interfacing with Printer, PC, PLC, remote display etc.
Data formats
Continuous, Fast Continuous, Printer, BSI Protocol or Modbus RTU
Baud rate
1200 / 2400 / 4800 / 9600 (Default) / 19200 / 38400 / 57600 bps
Length
7 or 8 (default) bits
Parity
Even, Odd or No (default)
Start / Stop bits
1 start bit and 1 stop bit
Address
Programmable between 01 …. 99
Max quantity
Maximum 10 instruments on the line.
Cable length
Maximum 1000m.
Table 4.7 – RS422 Serial Interface Specifications
Definition
RS422 Pin No.
RX+
6
RX-
7
TX+
8
TX-
9
Under the terminal
Table 4.8 – Pin configuration of RS422 terminal
RS422 serial connection is done with four wires as shown in Figure 4.9.
1 2 3 ………………… 10
Figure 4.10 – RS422 multi instrument connection with PLC
You may use RS422 port as a 2nd RS485 port after adding 2 short circuits between the terminal pins as
shown below.
1 2 3 ………… 31
Figure 4.11 – The second RS485 port usage of RS422 port (half duplex).
1
9