RS-232/422/485
Pin-outs & Signal Wiring
RS-232 Signal Pin-outs of DB-9 Male
Pin 1 |
DCD |
Pin 2 |
RxD |
Pin 3 |
TxD |
Pin 4 |
DTR |
Pin 5 |
GND |
Pin 6 |
DSR |
Pin 7 |
RTS |
Pin 8 |
CTS |
Pin 9 |
RI |
RS-232 Signal Pin-outs of 5-Pin Terminal Block
Pin 1 |
DCD |
Pin 2 |
RxD |
Pin 3 |
TxD |
Pin 4 |
DTR |
Pin 5 |
GND |
Only USB-COM PRO and USB-2COM PRO offer 5-pin
terminal block.
RS-422 Signal Pin-outs of DB-9 Male
Pin 1 |
TxD- (A) |
Pin 2 |
TxD+(B) |
Pin 3 |
RxD+(B) |
Pin 4 |
RxD-(A) |
Pin 5 |
GND |
Pin 6 |
RTS- (A) |
Pin 7 |
RTS+(B) |
Pin 8 |
CTS+(B) |
Pin 9 |
CTS- (A) |
RS-422 Signal Pin-outs of 5-Pin Terminal Block
Pin 1 |
TxD- (A) |
Pin 2 |
TxD+(B) |
Pin 3 |
RxD+(B) |
Pin 4 |
RxD-(A) |
Pin 5 |
GND |
Only USB-COM PRO and USB-2COM PRO offer 5-pin
terminal block
RS-422 Signal Wiring
l Point-to-Point 4 Wire Full Duplex
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RS-485 4 Wire (Full duplex) Signal Pin-outs of DB-9 Male
Pin 1 |
TxD- (A) |
Pin 2 |
TxD+(B) |
Pin 3 |
RxD+(B) |
Pin 4 |
RxD-(A) |
Pin 5 |
GND |
RS-485 4 Wire (Full duplex) Signal Pin-outs of
5-pin Terminal Block
Pin 1 |
TxD- (A) |
Pin 2 |
TxD+(B) |
Pin 3 |
RxD+(B) |
Pin 4 |
RxD-(A) |
Pin 5 |
GND |
Only USB-COM PRO and USB-2COM PRO offer 5-pin
terminal block.
RS-485 2 Wire (Half duplex) Signal Pin-outs of DB-9 Male
Pin 1 |
Data- (A) |
Pin 2 |
Data+(B) |
Pin 5 |
GND |
RS-485 2 Wire (Half duplex) Signal Pin-outs of
5-pin Terminal Block
Pin 1 |
Data- (A) |
Pin 2 |
Data+(B) |
Pin 5 |
GND |
Only USB-COM PRO and USB-2COM PRO offer 5-pin
terminal block.
l Point-to-Point 4 Wire Full Duplex
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l Multidrop RS-485 2-Wire Half-duplex
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