Arduino for STM32

I do not know any parts of your code, so I cannot tell you what might be the problem.
But I own some BT HC05 modules, so if you write a simple sketch I could eventually try to reproduce your problem.

Obviously, you are measuring the time to send data to Serial instead of setting bits. In this case you have to consider the properties of USB serial which works based on periodic interrupts which take place at fastest each millisecond. That is what your results mirrors, if the Serial USB does not bu...

There are examples for Tx and Rx using SPL here: https://github.com/JoeMerten/Stm32/tree ... USART/IrDA
You may try to adapt them to actual STM core.

G**gle is your friend: https://github.com/ukw100/IRMP

IMHO, the best method, even if not the most comfortable, is the manual installation, since the IDE can eventually change the board manager from one version to another, then you have to adapt the JSON file. The manual installation works for every IDE version. And you save a lot of time avoiding to un...

Maybe OS related? Have you tried in non-OS environment?
Or the UDP datagram you send is not correct?
If you post a simple (non-OS) example showing the effect I could eventually try to reproduce the problem and support you.

Well, for a throttle you do not necessarily need an extra circuit, a simiple e-bike throttle (like this ) uses a magnetic band which goes from 0 to middle position in the proximity of a HAL sensor. The reading is pure analog, you can use any magnet, and you can scale it in software according to your...

If only the flash and RAM size is the difference, you take the ld file for ZE variant and copy it as ZG variant in which you adapt the RAM and ROM LENGTH parameters. Then edit the boards.txt file by copying this section to the next following lines in which you change the name, the parameters accordi...

Which STM32F103 core? Arduino_STM32 (Libmaple) or STM32duino (STM official core)?

I have tested out with solely the IMU and displaying in the serial monitor, the same happens. Again, I need a simple sketch in order to reproduce the problem. Try to write one. In my experience, the issue gets understood by simplifying the software, or by using a simple working version and trying t...