Pixhawk 2.1 is a small cube, with a 38.5mm square footprint. All connection to the cube is via a DF17 connector coming out the bottom of the cube. This modularity allows for multiple form factors to suit multiple platforms. For the stand alone market, it will be coming out in two form factors to start with, a “Full” configuration, and a “mini” configuration. The full will have connectors for everything, the kitchen sink…. While the mini is restricted to the bare essentials.

The cube also has a massive quality advantage. Given that every single pin is available on the DF17 connection on the base, it allows complete factory full motion testing and calibration of each cube.

List of features changed on Pixhawk 2.1 from Pixhawk 1
 three IMU’s
 these consist of 2 on the IMU board
 1 fixed to the FMU

 two onboard compasses
 these consist of 1 on the IMU board
 1 Fixed on the FMU
 two Baros
 1 on the IMU (this Baro will most likely be removed in favour of a dedicated external Barometer.
 1 Fixed on the FMU
 Dual Power input
 This removes the option of redundancy from the Servo rail and replaces it with a dedicated second power plug
A dedicated power protection Zener diode and Fet have been added to protect from voltages over 5.6v being applied to Aux input 2
This is only on the “PRO” carrier board mini carrier board still draws the backup from the servo rail.
only 2 FMU PWM out channels on the Mini carrier board. (10 PWM total)
Dual external I2C
This allows for connection of items to either I2C port, potentially allowing two GPS / Mag units to be plugged in without the Mags conflicting.
GPS_Puck with Safety and LED
a single unit GPS / Mag / RGB / Safety button
Pixhawk 2 Hardware ID
I physical Hardware ID has been added to the I/O of the Pixhawk 2. This needs software to identify the board for debug purposes. This is the only non-software method to tell the two Pixhawks apart.
Breathing LED on cube. Comes on solid with default settings on the pin. Is connected to a PWM pin, and as such could be made to Breath,
Power monitoring pins are now routed to the I/O chip, these will allow for the logging of power events during an inflight reboot.
Brick OK, Backup OK, and FMU 3.3V are all connected to a digital pin on the I/O via a 220Ohm resister.