Installation guide

LMU Users Guide

V1.0.6 December 10 2009

- 90 - CalAmp Proprietary & Confidential

2=Read Response

3=Write Response

255=Error

• <msg body>

This field will be the list of parameters needed to comply with the <action>. This

field can be of variable length and is ASCII-Hex encoded. The exact format will

match the contents of the LM Direct Parameter message starting below the action

byte. Please refer to the LM Direct Reference Guide for details.

11.2.3 Serial Message Request

The SMS Serial Message Requests allow a user to send an SMS message to the LMU and

have the payload of that message passed-thru to a serial device on the LMU’s host port. This

feature is only available while the host port is in AT Command mode or, for the LMU-4100,

in MDT mode.

Send just payload to serial device:

!S0<payload>

This SMS message will force the LMU to send the <payload> contents to any device

connected to its host port.

Append <CR>+<LF> to payload

!S1<payload>

This SMS message will force the LMU to send the <payload> contents to any device

connected to its host port. The Carriage Return and Line Feed characters will be appended

to the end of the <payload>.