Moxa Technologies C168HS user manual Opt8B/C DTE Device DB25 Male

Type 3: To connect Smartio C168 Series to a DTE with 3-pin wiring.

If the “Hardware flow control” feature is set to “ON”, you must loop back (or short) the RTS with CTS and DSR with DTR, DCD on MOXA site, indicated in dash-lines of the following diagrams. If the “Hardware flow control” feature is set to “OFF”, you could just leave RTS, CTS, DSR, DTR, DCD open, ignoring the connection indicated in dash-lines.

Opt8A/S

PC COM2 port, Serial Printer, Terminal, or any DTE Device

Opt8A/S				DTE Device
DB25 Female				DB25 Male
RxD	2	2		TxD
TxD	3	3		RxD
GND	7		7	GND
RTS	5	4		RTS
CTS	4	5		CTS
DTR	20	6		DTR
DST	6	20		DSR
DCD	8	8		DCD

Opt8B/C

PC COM2 port, Serial Printer, Terminal, or any DTE Device

Opt8B/C			DTE Device
DB25 Male			DB25 Male
TxD	2	2	TxD
RxD	3	3	RxD
GND	7	7	GND
RTS	4	4	RTS
CTS	5	5	CTS
DSR	6	6	DTR
DTR	20	20	DSR
DCD	8	8	DCD

5-6Smartio C168H/HS User’s Manual