DIY GPS Module for Nikon DSLRs

Using a GPS Module, most modern Nikon DSLRs are able to automatically geotag pictures right when taking them. Unfortunately, the official Nikon GP-1 is very expensive (~200€). This project contains all necessary information to create a low-cost module which works just as well. This DIY version costs around 30€ (40$).

• Requirements
  • Tools
  • Parts
  • Electronic Components
• Building Instructions
• Technical Details
  • Nikon GPS Port Specs
  • Protocol
  • Schematics
• Images
• Sources

See also the Building Log.

Requirements

Tools

• Soldering Equipment
• Sharp knife to cut soft plastic
• A small dremel or similar to cut hard plastic
• Plastic Glue
• Screwdriver

Parts

Electronic Components

Building Instructions

1. Disassemble the remote trigger. If the cable has only 3 wires, you will have to cut the connector in half and rewire them to pins 3, 4 and 7. Use plastic glue and a vice to put the two connector halves back together after rewiring. Before rewiring, you can optionally shorten the cable to your desired length. Make sure to preserve the cable protection on the side of the trigger. We will reuse it for our GPS module.
2. Solder all electronic components onto the the PCB. I have done this in the order from largest to smallest, but do whatever is most comfortable to you. You might also want to consider reflow soldering, especially for the GPS module. If you do regular soldering, feel free to keep the ground pads on the bottom of the GPS module unconnected. I have done so and it does not cause any issues.
3. (optional, recommended) Do an electrical check of the PCB using a Multimeter. Make sure no pads are connected that shouldn't be connected.
4. (optional) Attach a 5V power source to the board (pads P1 and P3). Attach an oscilloscope to P2. You should see a burst of data coming in at about 1Hz, otherwise the pin should have a high level (+5V).
5. The PCB will be placed inside the lid of the case. Optional: use glue to attach the PCB permanently.
6. Use a dremel to cut a slot into the case with the width of the cable. Check if the original cable protection fits into the slot and adjust if necessary.
7. Shorten the part of the cable which will be inside the case and solder the wires to pads P1-P3.
8. Assemble the case by using the supplied case screws.
9. Go outside and check if the device operates properly. Note: it might take a while for the first GPS fix. Make sure to have a good visibility to the sky.
10. (optional) Use plastic glue to attach a hot shoe protection cap to the lid of the case (such that the GPS antenna will face upward). This will allow for a secure mounting of the device on the camera.

Technical Details

Nikon GPS Port Specs

• Proprietary 8-pin connector, pinout
• Operating voltage: 5V

Protocol

The camera awaits NMEA-compliant messages over the GPS DATA pin. Data is transmitted via UART with 4800 baud, no parity, 1 stop bit.

Schematics

The schematics and PCB layout was created using Eagle. You can find all required files in the eagle subdirectory. Additionally, the folder eagle-lbr contains a library of custom made components which are not part of the original Eagle libraries. Since the camera accepts raw NMEA data, the circuit is extremely simple and does not require additional controllers. The only difficulty is based in the operating voltage: the camera uses 5V while the GPS module operates with 3.3V. Therefore a voltage regulator and level shifter has been added to ensure correct levels on both sides.

Images

Sources

1. Peter Miller Photography
2. Homepage of Bálint Kis
3. Pinouts Guide