Installation guide

LMU Users Guide

V1.0.6 December 10 2009

- 36 - CalAmp Proprietary & Confidential

5.2

The Aux Port on the ioPOD can be used for one of two purposes, it can either be a source

for NMEA messages, or it can act as an MDT port. The mode of the Aux Port is controlled

by S-Register 160. If bit 0 of this register is cleared, then the port is setup for MDT mode. If

bit 0 is set, then the port is set up for NMEA mode (bit 0 is set).

Using the Aux Port

For MDT mode you would use:

AT$APP PARAM 1024,40,1,0

For NMEA mode you would use:

AT$APP PARAM 1024,40,1,1

5.2.1 NMEA Mode

The Aux port’s NMEA mode supports two NMEA messages, the GGA message and RMC

message. The GGA message is automatically enabled when NMEA mode is enabled. To

turn on the RMC message, you would use bit 4 of S-160. To turn the RMC message on, you

would set bit 4. That is:

AT$APP PARAM 1024,40,16,16

The RMC message is disabled by clearing bit 4.

AT$APP PARAM 1024,40,16,0

5.2.2 MDT Mode

The Aux port’s MDT mode is identical to the MDT mode of the Host Port. That is, you

may connect a serial device to the Aux port and be able to receive User Messages sent from

the serial device at your back-end system. The available settings for the Aux Port are similar

to those of the Host Port, so we only discuss the Aux Port’s settings below.

5.2.2.1 MDT Mode – Serial Port settings

The Aux port’s MDT mode serial settings are controlled by 2 S-Registers, 161 and 162.

Using these registers, a user can change the BAUD Rate, Data Bits, Parity and Stop Bits

settings for MDT mode.

The MDT mode BAUD Rate is controlled by S-Register 161 and supports the following

data rates:

• 4800 BAUD (ATS161=4)

• 9600 BAUD (ATS161=5)

• 19200 BAUD (ATS161=7)

• 38400 BAUD (ATS161=9)

• 57600 BAUD (ATS161=10)