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Sagem Sécurité document. Reproduction and disclosure forbidden.
SSE-0000053018-04
C
C
O
O
M
M
R
R
S
S
4
4
2
2
2
2
s
s
e
e
r
r
i
i
a
a
l
l
p
p
o
o
r
r
t
t
MA 500 / MA 500+ Series
OMA 500 Series
COM RS422/RS485
cable
1
Block 1
GND
Ground for RS422
Grey or White
2
Block 2
Tx-
Out
RS422 Negative Transmit
Orange
3
Block 3
Tx+
Out
RS422 Positive Transmit
Orange/White
4
Block 4
Rx-
In
RS422 Negative Receive
Green
5
Block 5
Rx+
In
RS422 Positive Receive
Green/White
RS422 interface is a full duplex communication.
C
C
O
O
M
M
R
R
S
S
4
4
8
8
5
5
s
s
e
e
r
r
i
i
a
a
l
l
p
p
o
o
r
r
t
t
MA 500 / MA 500+ Series
OMA 500 Series
COM RS422/RS485
cable
1
Block 1
GND
Ground for RS485
Grey or White
2
Block 2
Tx-
Out
RS485 Negative Transmit
Orange
3
Block 3
Tx+
Out
RS485 Positive Transmit
Orange/White
4
Block 4
5
Block 5
RS485 implementation is limited to half-duplex communication. So only Tx+ and Tx-
and ground reference signals are necessary.
Depending on the RS485 network, an impedance adaptation may be required.
For farthest terminal, a 120-Ohms resistor termination may be added to the terminal,
by strapping block 2 and block 3.
