GPS and Raspberry Pi
I ordered a 56 Channel GPS Receiver (GP-20U7) from hobbytronics. The GPS is made by SparkFun, its tiny as you can see below. So far it is working well and was easy to get working.
Cable things up
I guessed the pinout from the datasheet. Nothing exploded.
RPI -- GPS GND -> GND RX -> TX 3V -> VCC
The RPI comes with the serial pins bound to a TTY terminal. This lets you plug it into a USB-TTL cable and use screen to control the PI. To use the PI with a device that uses serial to talk you need to unbind it first.
T0:23:respawn:/sbin/getty -L ttyAMA0 115200 vt100from
Test and go
Check its working with screen, you’ll see the raw NMEA-0183 protocol:
sudo screen /dev/ttyAMA0 9600
Install and start gpsd:
sudo apt-get install gpsd gpsd-clients sudo gpsd /dev/ttyAMA0 -F /var/run/gpsd.sock
cgps -s for CLI, or
xgps for a GUI.
It took a good 15min for the first boot to get all the data. This is normal. After it was able to keep a solid lock inside next to a window.