This method is for short distances, maximum 3 meters.
Below you can see the wiring for a Datalogic DLS2000 infrared barcode badge reader.
±
5
V
1
2
V
G
N
D
D
C
F
IN
P
U
T
3
B
A
R
C
O
D
E
0
V
C
lo
c
k
D
a
ta
0
V
C
lo
c
k
D
a
ta
PROX2
PROX3
TIMEmate
power supply board
Connecting an external barcode badge reader
Relay1
Relay2
DLS2000
DATALOGIC
WHITE (VIDEO OUT)
BLUE (+5V)
BLACK + SHIELD (GND)