iLM 2500 Operational Description
The
i
LM 2500 Internet Location Modem combines GPS with a wireless data modem to provide
vehicle location specific information. The intended use is to monitor location, speed and travel
direction of vehicles. It is also designed to monitor PTO and activity based events such as
ignition status, door open/close and tow lifts. It provides a serial interface for computers and
peripheral devices like a printer, smart card reader, bar code scanner and temperature sensor.
Automatic Vehicle Location (AVL) System Diagram
System Description
The iLM2500 has a GPS receiver, which receives location specific information from satellites.
The GPS engine translates the receiving signal into data information and passes it on to the CPU.
The CPU computes vehicle location, based on the information received. The location data is sent
to the Rover Server/Database over the CDPD network. The information is retrieved via the
Internet. The data is updated at intervals defined by the user.
Hardware Description
The Main components used in iLM2500 design include Motorola’s MC68331 processor, Flash,
SRAM, Vista
chip set from @Road, RTC/System Controller, and various different 3
rd
party
CDPD OEM modules. Power to the system is drawn from a ve12VDC source. A few
voltage regulators use this source to generate power and supply it to different areas on the PCB.
The iLM2500 has a backup battery feature. The backup battery kicks in automatically when the
main power falls below operating voltage or is absent. The power supplied to external devices
via Data Port 1 and Data Port 2 can be switched ON/OFF by the CPU. This was added to
enhance power management.
