Installation guide

LMU Users Guide

V1.0.6 December 10 2009

- 77 - CalAmp Proprietary & Confidential

Short Message Service (SMS) is a communications protocol allowing the interchange of

short text messages between mobile telephone devices. SMS is supported on all CalAmp

devices except the iDEN LMU-4100™.

CalAmp LMU Interface – SMS

SMS is generally used as an alternative or as an augmentation to LM Direct. That is, SMS can

be used to:

• Report data

• Send remote requests to the LMU

• Re-program Parameters

While LM Direct tends to support more flexibility and functionality than SMS, SMS does

have one main advantage. SMS messages can be sent from any SMS enabled phone

where

LM Direct packets might be limited to a single server and period of time due to firewall and

routing rules. Of course the main disadvantage of SMS messages is that they are not logged.

The LMU will attempt to send SMS messages when requested, but, if they fail to reach their

destination they are lost.

The other important item to consider is that SMS only works for LMUs with internal

modems. Anything using an external or generic modem driver does not support SMS.

11.1

The LMU’s SMS capabilities support three mobile originate messages, the SMS Event

Report, the Text Status Message and Short and Long Text Messages The generation of each

of these messages is controlled by PEG and you should refer to the PEG Programming

guide for details. The following sections only describe the format of each of these messages.

Reporting Data via SMS

So long as your phone’s operator has an SMS exchange agreement with the network the LMU is on.