My thesis is about the development of a microcontroller-based GPS logger. The device is capable of showing the actual GPS coordinates and the traveling speed. It can also save the routes on an SD card therefore it is possible to display and process the routes with computer based mapping softwares.
As the basis of the device I chose Atmega644PA from the Atmel AVR microcontroller family which has a lots of integrated peripherals and relatively large program flash memory therefore further development and attaching other modules (e.g. a GSM module) will be possible.
As I was not familiar with the AVR family, at first I had to read the datasheet and understand the application and surrounding circuitry of these microcontrollers.
The display of the device is a HD44780 compatible LCD display and the GPS receiver is a SkyLab SKM53 integrated GPS module.
I built the prototype of the circuit using an Atmega128A development board. The software was developed on the prototype with special attention on portability among AVR microcontrollers. The Atmega644PA based hardware was developed in parallel.
For interfacing with the SD card I used the SD card and FAT filesystem library developed by Roland Riegel for AVR microcontrollers. I wrote a simple and portable library for handling the LCD display.