Hi forum,
I have a Holybro GPS M8N module with ist8310 compass.
I am trying to connect this GPS to my Kakute H7, GPS are working. But Magnetometer are not discovered by betaflight. Using BF 4.3-RC3 and 10.8.0 (for RC3)

Always get 9 I2C errors, maybe the issue are to be located here.
But Betaflight documentation Supported Sensors do not seem that Betaflight support IST8310 sensor.

Tryed to hack the GPS with U-Center (1/one has most control and protocol insight), but no scucces.

H7 board has this configuration, using uart 4 for GPS:
resource SERIAL_TX 4 D01
resource SERIAL_RX 4 D00
resource I2C_SCL 1 B06
resource I2C_SDA 1 B07
set mag_i2c_device = 1
set mag_i2c_address = 0
set mag_spi_device = 0
set mag_hardware = AUTO

Checked if barometer are the issue, disable don't help (has fixed the Baro hardware):
set baro_bustype = I2C
set baro_spi_device = 0
set baro_i2c_device = 1
set baro_i2c_address = 0
set baro_hardware = BMP280

Anyone has succes to setup betaflight to use this GPS/Compass with IST8310.
Are any of the listed sensors compatible (have tryed, no succces, but..) ?
A way to have it to work ?

Best regards HThuren

INAV seems to support the Compass: https://github.com/iNavFlight/inav/wiki/...or-support

This sensor was requested in Betaflight but it doesn’t seem they got too far: https://github.com/betaflight/betaflight/issues/5386

(13-Apr-2022, 09:00 PM)kafie1980 Wrote: INAV seems to support the Compass: https://github.com/iNavFlight/inav/wiki/...or-support

This sensor was requested in Betaflight but it doesn’t seem they got too far: https://github.com/betaflight/betaflight/issues/5386

Thx kafie1980 

I have viewed the compass scource at github, but too new in betaflight to start a patch branch (though an old C programmer) :-)
Found some documentation regarding HMC5883L/HCM5983 to IST8310 slave address, maybe someone can figure out if HW set to HMC5983 and can submit the prober address will work (I couldn't)

  IST831020User20Manualv15Eng.1457496818.pdf (Size: 1.6 MB / Downloads: 670)
  TE-DS-8310_8310 datasheet.pdf (Size: 698.29 KB / Downloads: 4,467)

Otherwise -howto request support of IST8310 in betaflight ?

The IST8310 is more complicated to auto detect because it has 4 different I2C slave addresses.

The magnetometer implementations in Betaflight are the simple/fixed hexadecimal based I2C devices and INAV seems to have a more robust code written for the IST8310.

I think its best you submit a request at Betaflight Github: https://github.com/betaflight/betaflight/issues

If they feel this is something that can easily be done then they will mark it as a feature request and will work on it at some stage (do not expect it to be implemented anytime soon unless the vendor requests and provides them hardware etc for testing.

You can also make your own Betaflight fork and implement the hardware and later merge it back to the main branch via a pull request.

(14-Apr-2022, 03:34 AM)kafie1980 Wrote: The IST8310 is more complicated to auto detect because it has 4 different I2C slave addresses.

The magnetometer implementations in Betaflight are the simple/fixed hexadecimal based I2C devices and INAV seems to have a more robust code written for the IST8310.

I think its best you submit a request at Betaflight Github: https://github.com/betaflight/betaflight/issues

If they feel this is something that can easily be done then they will mark it as a feature request and will work on it at some stage (do not expect it to be implemented anytime soon unless the vendor requests and provides them hardware etc for testing.

You can also make your own Betaflight fork and implement the hardware and later merge it back to the main branch via a pull request.

Ok, I'll do one or both :-)
Thank you

I have changed a Kakute F7 HDV AIO til Inav firmware to check out how I2C here do handle IST8310 as compass.
Most interesting are (according to the comments regarding clock speed at the attempt https://github.com/betaflight/betaflight/issues/5386 to support IST8310 in Betaflight).
In Inav you can setup the clock speed for I2C, ie. 400 Mhz, 800 Mhz or lower.

I believe this are a bigger change in both configuration and firmware, but maybe made for a reason, when having diffent FC with different clock speed.

I think that Betaflight’s I2C code does not allow tge ability to change clock speed for I2C communication and will need to be sorted out first.

If ever buying navigational components such as a GPS or Magnetometer or Barometer always best double check Betaflight to ensure support else the option will be to move to INAV.

Yes, your right. I'm beginner to the proper equipment. Then, I hoped to get the best of both worlds, speed and navigation. :-)

Anyway, for my spare Kakute F7 HDV AIO, I have ordered a SpeedyBee FS225 frame, a 4in1 ESC, reciever and a HCM5883 compass.

Then I have build the development enviroment for betaflight, forked betaflight firmware from github, puzzeled with the code, but stocked in magDev_s and magDev_t struct...
Maybe the future brings news.