My pixhawk hardware(pixhawk1) does not connect when rc.txt is in SD card.

I'm using the embedded coder support package for px4 autopilot.

When I do the calibration for pixhawk, pixhawk is connected with qgroundcontrol well and the led also worked well.

However, when I put rc.txt file into the SD card, pixhawk cannot connect with qgroundcontrol with error message : 'The vehicle is not responding' and the led light does not flash(off).

I think no flash led means that the pixhawk doesn't booted and I don't know why my pixhawk is not booted.

[R]

When you put the rc.txt file , pixhawk tries to load your simulink software and not the deafult px4 software

that means 2 things

1. the leds will blink only if you activated them in youre simulink app and build the code on pixhawk
2. for pixhawk to communicate with QGC when youre simulink app is active you need to have several additional lines in the rc,.xt:

mavlink start -d /dev/ttyACM0 -m config –x

mavlink boot_complete

Answer 1

[Arun Mathamkode]

Enabling MAVLink over Pixhawk USB will ensure the connectivity with QGC. Refer to this documentation.

[Ali Barari]

Hi,

How to enable MAVLink on TELEM1 for communicating (send and receive data) between groundstation simulink model and Pixhawk 4 in real-time?

[Ali Barari]

Regarding my previous question,

I don't know why i can't deploy this model to Pixhawk 4. Do i need to make some changes in rc.txt?

I just want to send sensors reading to a groundstation simulink model.

[Arun Mathamkode]

Based on my understanding, using MAVlink blocks in Pixhawk is not a logical usecase. PX4 already have 'mavlink' module which can encode and decode data and stream it through different serial interfaces of Pixhawk. The main usecase of MAVLink blocks is to use it on Host PC or on companion computer to read/write MAVLink messages. uORb messages are the way to communicate between different modules in PX4. Please refer to PX4 Architecture and uORB graph more more details. I would recomment you to enable the MAVLink stream on any specific serial interface you want to use, and PX4 will take care of encoding the MAVlink data and send it over that specifc interface. You can consider to use MAV_X_CONFIG parameter to enable MAVLink Telemetry. As per PX4 documentation, MAVlink is defaulty enabled over TELEM1 (MAV_0_CONFIG), if you use rCS as the startup script. From R2021b we recommend using the rCS as the startup script instead of custom rc.txt. You have an option to choose this in the Hardware setup screens from R2021b.