STM32 WM+ I2C

[Tectu]

You need external pull-ups for 100% sure. If there is any I²C Hardware on the STM32F100VL-Discovery board or you use external components which work, there are resistors on the discovery board itself.
Keep in mind that:

• 10kΩ --> 100kHz max
• 4k7Ω --> 400kHz max

And please double check and be absolutely sure that you do the open drain thing.


~ Tectu

[Fede]

Good morning! you're absolutely right! But after investigations I found that the WM + has already two pull-up resistors of 2k...
this is the reason because the VL works!
now I focus on the software...

[Fede]

OK!

PAL_STM32_OTYPE_OPENDRAIN does the trick!

THANK YOU ALL!

[Tectu]

You're welcome. The purpose of this discussion forum is to help other people
Enjoy your ChibiOS!


~ Tectu