17
(1) COM12: RS232/422/485 Ports
COM1/COM2 port can function as RS232/422/485 port. In normal settings
COM1/COM2 functions as RS232 port. With compatible COM cable COM1/COM2
can function as RS422 or RS 485 port. User also needs to go to BIOS to set
‘Transmission Mode Select’
for COM1/COM2 at first, before using specialized cable
to connect different pins of this port.
1 2 3 4 5
6 7 8 9
R
S2
32
D
C
D
#
R
S2
32
SIN
R
S2
32
S
O
U
T
R
S2
32
D
TR
#
G
N
D
R
S2
32
R
I#
R
S2
32
C
TS
#
R
S2
32
R
TS
#
R
S2
32
D
SR
#
Pin1
For RS422 Mode
R
S4
22
TX
-(B
)
R
S4
22
TX
+(A
)
R
S4
22
R
X+
(A
)
R
S4
22
R
X-(
B
)
(B
)
For RS485 Mode
R
S4
85
D
-(B
)
R
S4
85
D
+(A
)
