I2C-GPS NAV Navigation Board
Introduction
The I2C-GPS NAV module works with all 328P-based MWC flight controllers (with magnetic reluctance) to provide functions including GPS positioning, return-to-home, automatic waypoint flight, etc. For convenience, it’s recommended to be used with the CN-06 GPS receiver and the included wires, so you don't need to change the wires. The I2C port on the module can be connected to an anti-reverse cable, thus to easy refit the flight controller. Besides, it matches with any 10Hz GPS receiver with a baud rate of 11520.
1. Initialization: Blinks once per second, lasts about 6 times;
2. Waiting for GPS positioning: constantly brightens for 2 seconds, blinks for one second, and continues the constant lighting up, until the GPS positioning is completed.
3. GPS positioning completed: Blinks three times per second – from then on GPS-related functions are active for the flight controller, indicating at least 5 satellites are effectively connected.
Flight Controller LED Status Indication: In the locked (disarmed) mode, the LED blinks quickly when it's effectively connected to 4 satellites.
Note:
1) The Navigation Board must be used with 328P MWC Flight Controller which is equipped with magnetic reluctance (digital compass), and is better to include a barometer.
2) Before applying the Navigation Board, you need to enable the I2C-GPS function in the Multiwii firmware (recommended to use version 2.1 or above):
- define I2C_GPS// Enable I2C-GPS
3) Before use, set the Geomagnetic offset in the MWC firmware. If you ignore this step, the scale of digital compass and the GPS compass may be different, thus will impact the accuracy of the automatic returning-to-home. The offset differs between areas, please make the setting according to the actual situation. E.g. #define MAG_DECLINIATION 3.96f
