Arduino for STM32

Hello I have problems with the sparkfun dmp libary. https://github.com/sparkfun/SparkFun_MP ... no_Library

Lib runs fine on Sam21d (m0 without FPU)

on the 411 filter is not working correct. I think it is a problem of the FPU. Any suggestions ?
there are other libs witch have same problem. on device with fpu calculations are bad.

regards

Do you have an example which shows the bad calculation?
Any reference to other lib which have the same problem?
Which core do you use?
Which board?
viewtopic.php?f=2&t=301

thats not so easy to explain.
Board is a Blackpill with STM32f411.

[env:blackpill_f411ce]
platform = ststm32
board = blackpill_f411ce
framework = arduino

The code was written for the sam21d.
On sam after reset Kompass are fast in right direction. On the 411 compas starts count from 0 up to 50 degrees in about 10 seconds. Than is stabel but did not have the correct direction to north. there are no changes in code. I think there went something wrong when the fpu does the calculation.

I have a black F411 board, so I could eventually check, but without any example I cannot figure out what can go wrong.
I assume you use PIO. Have you tried with Arduino?
Again, which core do you use?

I have blackpill too.
I use VS Code with PlattfomIo. Using as standard STM32Duino
it makes no difference when I use arduino IDE.

The Sample from github is for a MPU9250. There a Quaternions and Kalman Filter calculated. So my thought is a problem when compiler use FPU.

My 2 cents is that some rounding in the operation...

fpiSTM wrote: ↑Sat Oct 17, 2020 3:45 pm My 2 cents is that some rounding in the operation...

Maybe but why only when using fpu ?

is it possible to say the compiler not to use the fpu?