IDEC MICROSmart FC6A Series User Manual page 178

2: P S
RODUCT PECIFICATIONS
Wiring Example When Using Both Ports
RS232C
Interface
Device
The serial communication module is equipped with two serial ports, and serial communication can be performed using both serial
ports simultaneously. RS-232C or RS-485 can be selected and used for each port.
Above wiring example shows RS-232C communication with the upper side port and RS-485 communication with the lower side
port.
Notes:
 A single port cannot be used as RS-232C and RS-485 simultaneously.
When communication conditions are unstable, add terminating resistance matched to the characteristic impedance to both ends of the cable.

Use resistance with a rating of 1/2 W or higher.
2-142
Upper Side Port
FE
Shield
Lower Side Port
FC6A S MICROS
ERIES MART
Terminal No.
RS1(RTS)
ER1(DTR)
SD1(TxD)
RD1(RxD)
DR1(DSR)
SG1
NC
A1
B1
Terminating
Resistance
SG1
Terminal No.
RS2(RTS)
ER2(DTR)
SD2(TxD)
RD2(RxD)
DR2(DSR)
SG2
NC
A2
B2
SG2
FE
U ' M FC9Y-B1722
SER S ANUAL
RS485
Interface
Device
Shield
Terminating
Resistance
RS485
Interface
Device