User's Manual

Table Of Contents

4000/5000 Modems’ User Guide

GPS Store & Forward

The 5000 series modems have an integrated 512Kbytes Static RAM memory

dedicated to storing GPS fixes. It can store an average of 5000 points (position fixes),

depending on the protocol selected. Its purpose is to keep a record of the vehicle’s

route when the reporting destination is unreachable. Under such circumstances, the

modem stores GPS data in a static memory in a First In First Out (FIFO) manner.

When the wireless connection is re-established or when the socket at the reporting

destination is re-established, the modem resumes sending GPS packets. If the

memory is full, the new fixes overwrite the oldest stored ones based on a FIFO

process.

Refer to the table below as a guide in calculating the total storage time and size of

related packets.