PaulS:
Really? How will you control this? There isn't, typically, a "search for satellites" command that you send to the GPS. It searches for them when it feels the need, and it isn't going to tell you when it feels the need.
I read somewhere that 4 satellites are needed to get an accurate location. I mistakenly thought that once it had 4 satellites (which I can read from the NMEA data that is being spit out), that it would come out of "search" mode.
The arrival of serial data does not, normally, wake a sleeping Arduino.
I was going to use this tutorial: https://rubenlaguna.com/post/2008-10-15-arduino-sleep-mode-waking-up-when-receiving-data-on-the-usart/
Sleeping the Arduino, which uses very little power, while the GPS is sucking up power like there's no tomorrow seems a bit silly.
Probably right......I was thinking about battery life and trying to maximize it.
The 329-based Arduinos are typically 5.0V devices, unless you clock them at half speed - not a beginner project. Is the GPS a 3.3V device or a 5V device? Most are 5V devices.
I was going to use an mega328 with an arduino pro (8 mhz) boot loader. The GPS and SD card both run on 3.3v so I figured it would just be easier to run the mega328 at 3.3 volts as well rather than level shifting everything. I have a few other threads that I started to work through the issues associated with running an arduino at 3.3 volts. I'm putting together the schematic in Eagle now and am hoping to post it on here before I send the board out to be made.