I want to build small data logger for our plans. We want to use it on light gliders so every additional gram and mm has great importance. It should be really small, like 50*40*5 mm or less ( I talk about the size of the full device with GPS) and write all data that characterise the movement on microSD card.
No communication is required. I need only separate log-file for each flight.
Working behavior should be smth like:
1. Power On the device
2. Start record the track (by signal from IO pin)
3. Collect flight data and write it to microSD card
4. Power off the device
5. Be able to download files from the device over bluetooth (just a feature)
6. Most important - device should be really small and work for a long period (>5 hours) from 1s 250~400mA/h battery. (really as long as possible)
some first questions that I have:
A. Is it a good idea to develop a specific board for this purpose?
B. Does it make sense to rewrite a project for other CPU (currently it supports ATmega1280, ATmega2560, stm32F4 but they need to much power). Is it possible to build project for STM32L151CBU6 (L means low power).
C. Is this code suitable for a device that run on really low power mode (CPU mostly slips or uses DMA if CPU can)
D. How the device will act for first 30-60 seconds with cold GPS? Can it track the motion just after we powered it on?
I've configured Atmel Studio and successfully built latest APM Planner for 2560 but it's not exactly what we need.
Can somebody help me to select proper hardware and change software accordingly to requirements, with ideas about power consumption in mind. I'm ready to work and ready to pay for help also.