I've built a few projects with GPS. In general I've found that it's hard to upload a sketch when the GPS is connected to my arduino and powered. If I disconnect I can flash the sketch, then re-connect and it will work.
I connect to TX/RX. Is this related to the serial connection of an arduino to my computer?
Also, I'm trying to integrate an MP3 player shield with GPS. The sketch I'm using lets one pick songs in the serial terminal. When I add the GPS the serial terminal goes nuts. It's like it's getting random commands.
What is going on?