Voxl2 Mini i2c

tiralonghipol

Hi,
Im testing the command i2cdetect with the magnetometer attached on J19 as swhon here
but I get a weird output:

voxl2-mini:/$ i2cdetect 0    
Warning: Can't use SMBus Quick Write command, will skip some addresses
WARNING! This program can confuse your I2C bus, cause data loss and worse!
I will probe file /dev/i2c-0.
I will probe address range 0x03-0x77.
Continue? [Y/n] y
     0  1  2  3  4  5  6  7  8  9  a  b  c  d  e  f
00:                                                 
10:                                                 
20:                                                 
30: -- -- -- -- -- -- -- --                         
40:                                                 
50: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 
60:                                                 
70:

I tried to look it up on the web but I do not seem to find any solution for properly probe the bus. Any help?

system details:

system-image: 1.7.1-M0104-14.1a-perf-nightly-20231025
kernel:       #1 SMP PREEMPT Thu Oct 26 04:23:26 UTC 2023 4.19.125
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hw version:   M0104
--------------------------------------------------------------------------------
voxl-suite:   1.1.1
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Eric Katzfey

@tiralonghipol i2cdetect is looking on the applications processor. The i2c on J19 are routed to the DSP, not the applications processor.

tiralonghipol

@Eric-Katzfey thanks for your answer

so what could be a way to check if I correctly detect a i2c device on J19? assuming of course wiring is correct

Eric Katzfey

@tiralonghipol If you run PX4 and have a supported magnetometer attached to J19 then you can see if the magnetometer driver is sending out magnetometer data. (e.g. px4-listener sensor_mag).

tiralonghipol

@Eric-Katzfey what I am trying to do is writing a driver for an external i2c imu
is there any code example where you have already implemented an i2c interface on the dsp on voxl2 mini?

Eric Katzfey

@tiralonghipol For PX4? Then yes, take a look at some magnetometer driver code: https://github.com/modalai/px4-firmware/tree/main/src/drivers/magnetometer/isentek/ist8310

tiralonghipol

@Eric-Katzfey amazing, thank you!

tiralonghipol

Hei @Eric-Katzfey

is there any code example to read the J19 i2c port 'outside' px4 ?

Eric Katzfey

@tiralonghipol No, only within px4