Ryan M Sutton

I didn’t change anything with the electronic parts, but did get a new case for the data logger.  I tried long and hard but could not find a way to fit the GPS antenna inside the case.  The Molex connector goes to the  status LED and switch shown earlier.  The switch I changed from being a run/stop switch to just switching power, which allows me to get everything packaged up the night before. The usual status LEDs are inside the case, but are not visible during operation, which seems to be ok.

The board doesn’t line up with any of the mounting holes, even REV:B which I added mounting holes do not line up, I am pretty sure I can modify the board to fit these mounting holes though.  Over all this case it larger then I would like, hopefully with some other modifications I can get the size down a bit.  Putting it into this case did stabilize the device quite a bit, I had a good run which I will talk about in another post where it did not reset all day and churned out some very nice data.
 

I’m now back to the same functionality I had on the version I built on proto boards though now much smaller. I added a run/stop switch on the side. Each transition from stop to run will result in a new file being started. Two lights on the top, the green one is lit when the uC is in a ‘RUN’ state, the red one flashes after each track point is written to the SD card.

Since the plan is to use this while skiing I used a LilyPad wearable switch and LED sewn into a glove for status and control. The LED is just a duplication of the SD write led on the case. As long as it is blinking, there should be data being written to the card. Each push of the switch will result in a new track segment started ( and the old one closed ).  I couldn’t find any of my LED LilyPad stuff so I de-soldered one of the switches and mounted a 1206 LED across the pins. The glove is connected back to the main box with a three conductor ribbon.
Hopefully will be trying this setup out tomorrow, interested to see if it actually works.

After having the boards for at least a month I finally built one up.  This board dosn’t really do much new it is basically my GPS logging hardware v3.1 built onto one board.  Since I was building my own boards I opted to use a atmega1284p since I was having issues running out of sram before (though I did clear that up in software).  So there are two atmega1284p processors one to deal with the GPS and sensors, and another to talk to remote sensors as well as build and write the GPX file to the SD card. I also added an accelerometer and gyroscope to add to the data the sensor uC is collecting, I will probaly replace the atmega1284p on the sensor side with a atmega88 if the memory utilization is low enough, the 1284 seems a bit overkill for what it is doing.
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