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Etm9420_9440_Quick_Start_Guide
201705RV01
Interfaces
RJ12 Power Supply
Pin
Function
Looking at Modem Socket
1
Power Supply (+6 to +35VDC)
2 Not
Used
3 Power
Down
4 Ignition
5 Not
Used
6 GND
DB9 Female Serial (RS232) Port
Pin
Function
1 DCD
Out
2 RXD
Out
3 TXD
In
4 DTR
In
5 GND
6 DSR
Out
7 RTS
In
8 CTS
Out
9 RING
Out
USB Port
Function
USB Port
4-pin (female) USB-B connector
Combined RS232 Serial & Power Input (in lieu of USB Port - fitted to some older units)
This port is connected in parallel with the above RJ12 (power) and DB9 (serial) interfaces. This
connection is commonly used for a single interface with electricity meters.
Pin
Function
Looking at Modem Socket
1
Power Supply (+6 to +35VDC)
2 DCD
3 DTR
4 GND
5 RX
6 TX
7 CTS
8 RTS
Caution
This modem has an inactivity timer/reset on the serial port,
this can cause issues with applications using the USB - the
application software may not recognise the USB after
reset. Contact ETM for guidance.
