Welcome to EnviroDIY, a community for do-it-yourself environmental science and monitoring. EnviroDIY is part of The EnviroDIY GPSbee is an easy way to add GPS capability to any device that is compatible with the standard Bee footprint. It’s built around the popular MTK3339 GPS module, can be powered with either 3.3v or 5v, and uses around 20mA when operating. The module has a built-in antenna, but the board also has a separate u.fl jack for an optional external passive antenna.
There’s a coin-cell lithium battery socket on the bottom where you can add an optional 3v CR1220 battery to keep the internal clock alive whenever the board isn’t powered, which allows the module to get a much faster fix when powered up.
The GPSbee has two solder jumpers on the back. The default setting for both is “open,” so you’ll need to solder a blob of solder across either one if you want to “close” it. Closing SJ1 lets the green “FIX” LED blink while the board is acquiring a fix (it goes out once you get a fix, so the LED only shows you when the module is trying to get a fix).
The other jumper (SJ2) selects how you want to control the power supplied to the GPSbee. The default setting (open) keeps the GBSbee OFF and turns it on only when you set Bee socket pin 9 high (controlled by Mayfly pin D23).
So if you are using an EnviroDIY Mayfly board with the GPSbee, your Mayfly code can turn the GPSbee ON or OFF as needed, depending on what the rest of your code is doing. However, if you’re using the GPSbee with something other than a Mayfly, or you want the GPSbee to be on anytime power is applied to the Vcc pin (pin 1), just short out the SJ2 “ALWAYS ON” jumper and the GPSbee will stay on.
The EnviroDIY GPSbee uses the same series of GPS units that are used on the Adafruit Ultimate GPS board, so if you’re looking for code examples, the easiest thing is to use Adafruit’s library that they guarantee works with that module.
If you use the GPSbee with an EnviroDIY Mayfly, just plug the GPSbee into the Bee headers on the Mayfly, and it’ll be connected to the Mayfly’s second hardware serial port (Serial1). You can use this sketch from Adafruit’s library as-is, with no changes needed.
If you didn’t short out the “ALWAYS ON” solder jumper, you’ll need to add the following two lines at the beginning of your “void Setup” function:
pinMode(23, OUTPUT);
digitalWrite(23, HIGH);
If you’re using the GPSbee with anything other than an EnviroDIY Mayfly, you’ll need to figure out the proper wiring for your device or adapter. The GPSbee only needs connections on 4 pins of the Bee header (or 5 if you want to control the power as mentioned above). Bee Pin 1 is Vcc, Pin 10 is Ground, and Pins 2 and 3 are serial RX/TX. See the schematic below for the EnviroDIY GPSbee wiring details.
