User's Manual

Page 25

M Series Data Radio – User Manual

Part E – Getting Started - MR450

User Interface

The user port is wired as a RS232 DCE, configured for no

handshaking (3-wire) interface.

Only 3 wires need to be connected between the radio and the

application device.

Typical pins used:

• Pin 2 (RxD) - Data Output from Modem.

• Pin 3 (TxD) - Data Input To Modem .

• Pin 5 (SG) - signal ground.

See Part D – System Planning and Design - Data Connectivity, for

further details of other cable configurations.

RS232 Connector Pin outs (DCE)

Port A, Female DB9

Activating the Transmitter

In most systems, the transmitter by default is controlled automatically

by the radio when it has data to transmit.

To manually activate the radio transmitter, connect (ie: link) the RTS

signal (Pin 7) to Aux (Pin 8).

To operate in this mode, the radio must be configured via the

programming software for PTT from RTS.

Caution: Ensure a RF load is present BEFORE

transmitting.