Crazyflie2 issues

Dear all,
I have a question about CF2 with px4. CF2 platform has a nrf51822 which also is programmable. Does px4 include firmware of this module? Or, it just use original CF2 firmware for this module. @dennisss

It’s made to use the original firmware ( and replicate the original protocol which works pretty well (with a MAVLink layer on top of it). As far as I know, there isn’t any compelling reason to change it unless you have another NRF51 transmitter you want to connect to it in which case it would support larger packet sizes compared to the NRF24 based Crazyradios the original firmware is made for.

I have an additional question about the SD card. PX4 will try to check and mount the SD card at Nuttx startup, while Cf2 does not have an SD-card. Could you tell me how this is handled in the PX4 firmware for CF2?
EDIT: also, what firmware should I use? Can I use QGC and directly flash CF2 after flashing bootloader? Or, I need to self-compile the firmware, if so, which branch on github should I use?

It will try to mount the sdcard but will gracefully fail and continue on without it.

Until I get around to adding in support to QGC, you need to manually compile the firmware. Master branch works fine. See for the build commmand

Thanks for the reply.
I get it. And, Ah, I have connected Cf2 to QGC and use a joystick for flying. However, after I calibrated all sensors and the joystick, I cannot make it fly. Should I arm it first like other px4 hardware? Here is my environment:
(1) QGC running on ubuntu16.04
(2) CrazyRadio connected to the aformentioned ubuntu16.04
(3) Joystick: microsoft X360.
(4) CFbridge installed.

Yeah, arming procedure is the same. Typically it means holding the left stick down and to the right for 5 seconds

I still cannot arm it and make if fly. I use QGC to see the joystick status as the following figure. Once I want to arm it, I couldn’t stick yaw to the maximum and throttle to the minimum, because joystick is a circle at this point . How can I arm it then?
Also, @seth

The throttle looks to be at the minimum. QGC just shows it that way (slightly higher than min in the latest version). As a general PX4 rule, it won’t arm if the radio and flight modes aren’t setup. You should calibrate the radio using the joystick.

I tried it. However, I cannot calibrate the radio using joystick. The radio does not respond. Did I miss something?
Besides, I got confused that I already can calibrate the joystick, why do I still need to calibrate radio? As you see, the left column has ‘joystick’ item for us to calibrate.
Also, I saw that in src\drivers\boards\crazyflie, there is no relevant code for configuration of GPIOs like for other px4 hardware in their corresponding folders, i.e. px4fmu-v4. They all call px4_arch_configgpio in nsh_archinitialize() function; however, I do not find it in CF2. How does CF2 config GPIOs of the board?