2.
Interface Illustrations
2.1 Rear panel
Port
Physical interface
Description
①
RS-422
Control output
(Ta,Tb,Ra,Rb)
•
Connect with RS-485:
Ta -> RS485+; Tb -> RS485-
•
Connect with RS422:
Ta -> RXD IN-; Tb -> RXD IN+
Ra -> TXD IN-; Rb -> TXD IN+
②
Ground
Ground (G)
Signal control line to ground
③
PW
Power indicator light
The light is always red when keyboard is working
④
TXD
Sending data indicator
light
The light will flicker in green when the unit is sending data
⑤
RXD
Receiving data indicator
light
The light will flicker in green when the unit is receiving data
⑥
DC-12V
Power jack
DC12V power input
2.2 Wiring diagram
Connection with surveillance dome cameras:
3
