I'm the newest of the newbys! I'm going to tackle what seems to me as a very difficult project. I want to receive 2 GPS sentences, GPRMB and GPRMC from my humminbird depthfinder/gps and use them to control a simple relay. I have purchased a mega 2560 and a 2 relay shield. Can anyone point me in a direction to learn what I need to make this a reality? I have been reading everything I can find for the last 4 days but nothing seems to relate to the gps output similar to a fishfinder output. I have been able to construct simple (working) sketches but can't seem to get the gps sentences to even flash LED 13. I'm starting to get the feeling that the saying about "old dogs and new tricks" might just be correct. Any help or guidance I can get will be appreciated and yes, I have been reading and playing with the playground as much as possible.
Thank you in advance for helping bring an old man into a new world.
Do you have any links to documentation for your device?
http://store.humminbird.com/media/document/798c-ci_Manual.pdf
I havent been able to find anything about the NMEA out voltage, I've tried to use a digital voltage meter to get a reading on the output voltage but it will not show any voltage. The unit operates on 12v dc and I can input the gps signal directly into my laptop via my serial input and show sentences using a program already installed,( Drdepth)
Your description sounds like the interface is RS232, so you'll need a level converter/inverter like a MAX232 to allow it to talk to an Arduino.
I will google that little jewel right now, thank you!
Thank you guys, that little jewel did the trick, I can now make the LED blink when receiving GPS signals, a very small step for yall but HUGE for me, LOL! Now, onward and upward in the world of arduino!