Radio Calibration problem

[Tjohoansson]

Hey Mr. Hefny!
We have some problems that we would like some help with..
When we connect to Mission Planner and start Radio Calibration, nothing happens. No green bars are visible at all..
We use a raspberry pi zero 2 w with buster and
Flysky FS-i6X i6X 10CH 2.4GHz AFHDS 2A RC Transmitter With FS-iA10B Receiver
We have measured the inputs on the raspberry with an oscilloscope and there is a signal.
We do not use the GY-91 version.
Do you have any ideas or tips that we can try?
Sincerely.
/ Anders and Albin

[usbalbin]

To add some more info

In our last attempt we used the image recommended from this comment and a precompiled obal 4.2.2 binary with the preperations from this video except the compilation part since we used the precompiled binary.

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In the attempts before that, we ran bullseye and tried to compile from source natively on the pi zero 2 w with the exact same result. All meters "empty" in the radio calibration screen.

In addition to read the pins with an oscilloscope to confirm the transmitter actually sends pulses to the pi, we also made a small bash script to read the pins. While the scripts is too slow to show the curveform, it does show that the inputs does change.

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Other than that we have also tried to cross compile ardupilot as is done in the video however running the generated binary on the pi produces a segfault as soon as mission-planner tries to connect. I do not have the link to the exact crosscompiler version used but I believe it was one of these...

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Is there anything obvious we might be doing wrong? Or something to double check, missing info etc., please let us know :)

/ Albin and Anders

[Tjohoansson]

Good morning!

We have built the original version and used the cards you specified:
16 Channel 12-bit PWM/Servo Driver-I2C interface PCA9685
16 Bit I2C ADS1115 Module ADC 4 channel with Pro Gain Amplifier RPi
GY-68 BMP180 Replace BMP085 Digital Barometric Pressure Sensor Module
MPU-9250 GY-9250 9-axis sensor module I2C/SPI Communications Thriaxis gyroscope

We will check the i2c & spi configuration!

Thanks for your help!

[Tjohoansson]

Good morning!
Now we have both checked i2c and spi without results..
We will solder a new board to check if it is some of the sensor card that is not working..
We will never give up!

[HefnySco]

Please use python code to run it on your RPI and test the sensors while soldered on the PCB (OBAL). This will confirm if soldering and sensors are good or not.
If sensors are working and ardupilot firmware is running then it should work fine. but first confim using python test code running on RPI.

[usbalbin]

Thanks!

Any hints on where too start looking for such code?

[HefnySco]

Please note that Bulleye64 Need to be compiled to enable CONFIG_STRICT_DEVMEM check this link .
Also please compile ardupilot master code as there is a bug in the last release. The newer release includes the fix already.

[usbalbin]

Measuring on GPIO5 (CH1) on the raspberry, as far as we can see, everything looks as it should.

And the pulse width changes from 1-2ms depending on stick position on the controller.

[HefnySco]

Hello,

1- Please run OBAL from command prompt and make sure that there is no problems in reading the sensors (IMPORTANT)

2- Are you using PPM,PWM ?

Also please make sure you compile master version of ardupilot not release. as I believe this fix is not merged yet
https://github.com/ArduPilot/ardupilot/pull/23943

[usbalbin]

Thanks a lot for the answer :)

We are using PWM, the remote and receiver support both, and we tried both settings with no difference. We also verified the settings with the oscilloscope. With that said, PWM was the plan.

I do not have a screenshot but there were warnings about the barometer

[Tjohoansson]

Good news Mr. Hefny!
Our barometer card was broken!
Now we have changed and everything seems to work fine!
Finally!