IO Connector Signal Descriptions:
DB9 RS232 Female Connector:
Note 1: Pin 1 optionally connected to +VCC () if PCB pad labeled “DB9 PWR” near DB9
connector is bridged. This may be bridged by the OEM or by us if you require this feature.
AUX Connector:
You may optionally connect an off board speed selection switch, DB9 serial connection
port or ambient light sensor.
Note 2: Contact us for the part number and hookup schematic for the light sensor. Two different types of
sensors may be used, passive LDR or active IC (recommended). Internal light sensor must be disabled by
removing R24 on the front of the PCB in order to use an external light sensor.
Note 3: You may also connect an external BCD rotary switch or thumbwheel switch to use in place of the
on-board rotary switch. In this case the on-board switch must be set to the “0” position or removed at the
factory.
Connector
Pin #
Signal
Name
Direction
(wrt Radar)
Description
1
+VCC
Note 1
PWR
Note 1
Radar VCC (battery “+“ terminal)
Note 1
2
RS232 TX
OUT
RS232 Serial port TX pin from sign
3
RS232 RX
IN
RS232 Serial port RX pin into sign
4
N/C
-
Do not connect
5
GND
PWR
Signal/PWR Ground
6
N/C
-
Do not connect
7
N/C
-
Do not connect
8
N/C
-
Do not connect
9
N/C
-
Do not connect
Connector
Pin #
Signal
Name
Direction
(wrt Radar)
Description
1
Vext0
Note 2
IN
Note 2
External Light Sensor Input
Note 2
2
+ VCC
PWR
Connected to input supply v
3
B1
Note3
IN
External BCD speed switch B1 pin
Note3
4
RS232 RX
IN
RS232 Serial port RX pin into sign
5
GND
PWR
Signal/PWR Ground
6
RS232 TX
OUT
RS232 Serial port TX from radar
7
B4
Note3
IN
External BCD speed switch B4 pin
Note3
8
B2
Note3
IN
External BCD speed switch B2 pin
Note3
