Nedap uPASS REACH - Rs422 Connection

UPASS REACH | INSTALLATION GUIDE
Connections
14/35
3.4.5 RS422 CONNECTION
The uPASS Reach reader has an on-board RS422 interface. The RS422 interface is
similar to the RS232 interface. It shares the same communication protocol. The
RS422 interface is commonly used when longer cable lengths are required.
Connections:
RX+
Receive line (positive)
RX-
Receive line (negative)
GND
Ground
TX+
Transmission line (positive)
TX-
Transmission line (negative)
RX+ and RX- inputs are terminated with a 120Ω resistor.
TX+ and TX- must be terminated at the host side.
TX-
TX+
GND
RX+
RX-
HOST
Figure 16: RS422 wiring
Note
The RS422 interface is
disabled while the USB
interface is in use !!!
Enable the on
-
board RS422
interface by setting DIP
-
switch SW1
-2 to OFF. See
chapter
4.1 for details.
Optionally select the
TRANSIT compatible
processor with DIP
-switch
SW1
-1.
Maximum cable length
1200 meters (4000 feet).