Hi, all --
I'm pretty new here and pretty new to Arduino. I am trying to build a GPS datalogger that displays a piece of data on a multi-digit 7-segment LED display. The idea is to use it for sailing, locked up in a clear waterproof box. Having the GPS datalog will help us analyze performance off the water and having a display (probably of current speed) will help us see how we're doing in real time.
I'm essentially trying to emulate this product: http://store.velocitek.com/SpeedPuck , though I will not be able to do the wind graph and the GPS module recommended in the lady ada kit has slightly lower specs (notably the amount of data per second). But still, it will be about half the price, with most of the functionality!
So, to that end, I built the LadyAda GPS datalogging shield, which is working well. It's been a lot of fun to learn about NMEA and everything.
Now the hard part: hooking up a big 7-segment LED display. I bought an alarm clock for $15 and opened it up, but now I'm at a bit of a loss. The display is a solid 1.85" (has to be big to be seen on the water...) and runs off an LM8650 clock chip, datasheets for which are available online, but I'm at a bit of a roadblock and would love some help in how to proceed. As a side note it's kind of fun to trace where these components come from...I managed to find the PCB factory in China that made the board through Google Translate....
I think probably the next step is to buy a multimeter (i know, i know) and poke at some pins and see what lights up. That would be satisfying, but I'm still missing the link between functioning display and arduino, much less functioning display and my current velocity data.
I also obtained a free sample (!) of a raw 7-segment LCD display, but got scared off by the AC requirements, lack of an IC driver, etc.
Any guidance would be much appreciated.