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© 2012 by RF Monolithics, Inc. DN-900 Series - 07/30/12
Ref Name I/O Description
T +PWR I The center coaxial conductor (tip) is the positive DC power input.
R GND - The outer coaxial conductor (ring) is the DC power ground.
G PWR O Green LED indicates the unit is powered.
A LINK O Amber LED indicates the unit is linked.
DN-900G Serial Port DB9 Connector Description
Pin Name I/O Description
1 DCD O This pin is an output indicating the modem is linked to the radio network.
2 RADIO_TXD O This pin is the DN-900G serial data output.
3 RADIO_RXD I This pin is the DN-900G serial data input.
4 DTR I This pin is the data terminal ready input from the DN-900G host.
5 GND - This pin is signal ground.
6 - - No connection.
7 HOST_RTS I This pin is the request to send input from the DN-900G host.
8 HOST_CTS O This pin is the clear to send output from the DN-900G.
9 - - No connection.
Pin Name I/O Description
1 +PWR I This terminal is the positive power supply input, +6 to +24 V.
2 GND - This terminal is a power supply and signal ground.
3 485 EN I
When this terminal is unconnected, serial operation is RS-232C. When this terminal is grounded
to terminal 2 or 4, serial operation is RS-485.
4 GND - This terminal is a power supply and signal ground.
5 TX/A O This terminal transmits data to the host (RS-232C TxD or RS-485 A signal).
6 RX/B I This terminal receives data from the host (RS-232C RxD or RS-485 B signal).
DN-900G/DN-900U Power Connector and LED Description
DN-900I Serial Port Terminal Block Description
