Just a quick update to say that my teenage electronics dunderhead brain is now well and truly fixed!!!
Managed to get an Airbot provided U-Blox 6M GPS unit connected to my Gertboard and Raspberry Pi – and I can see NMEA messages fine over minicom!!!
Here is a pic of the data received:-
I did this with a Raspberry Pi V2 connected directly to a Gertboard, with the following procedure:-
- Connect jumper on top two pins of J7 on Gertboard to send 3.3V to components on board (may not need this, but I didn’t want to risk frying the GPS chip) (This will also light your Gertboard up like a Christmas Tree!)
- Connect GP14 (TXD or Transmit) pin on Gertboard to Breadboard row 14
- Connect GP15 (RXD or Receive) pin on Gertboard to Breadboard row 15
- Connect provided cable to GPS unit – this gives you a 5 pin (4 connected) output, and a 2 pin output
- Connect cable PIN 3-black (TXD or Transmit) to Gertboard row 15 (yes 15 – TX of GPS needs to go to RX of Gertboard)
- Connect cable PIN 2-orange (RXD or Receive) to Gertboard row 14
- Connect cable PIN 5-white (GND or Ground) to GND row on breadboard
- Connect cable PIN 1-yellow (VCC or Voltage) to V3 row on breadboard
- Connect breadboard GND row to any GND pin on Gertboard (I used left hand of board column 2 (GND), top PIN
- Connect breadboard Voltage 3 row to first 3.3V pin on top left of Gertboard
Now install minicom by doing:-
sudo apt-get install minicom
And execute the command:-
sudo minicom -b 9600 -o -D /dev/ttyAMA0
You will see the NMEA messages like the ones in the image above!!!
Below is a picture of my setup:-
Note I’ve used a mixture of the leads that come with the Gertboard and simple breadboard jumpers to connect all the components. A bit hacky, but works great!
Components I’m using:-
- Raspberry Pi V2
- Gertboard V 21 Oct 2012
- Airbot UBlox 6M GPS unit with built in digital compass – http://shop.myairbot.com/index.php/neo-6m-ublox-u-blox-gps-module-for-mwc-apm.html
- Minicom software on Raspberry Pi (Raspbian)
- Generic breadboard from Maplin
UPDATE 25/Jun/14
I’ve used the great and free Fritzing tool to diagram my basic connections. Hopefully more clear than the above text and picture:-
FYI There’s a great NMEA online decoder at http://freenmea.net/decoder