Why HAL_I2C_Mem_Read returns only 0?

[ATavo.1]

Hi,

I am using stm32f1 and HUT21D sensor (Temperature and humidity sensor). The sensor use i2c for communication.

I am using IAR and cubeMX.

For cube: I used default setting for i2c.

For IAR: I shared the main.c below.

Can anyone help on why only get 0.

#I2C​ #[STM32 MCUs]​ 

[ATavo.1]

I have a question. Sometimes I get HAL_OK and Sometimes I get HAL_Error. Is the problem with wires or not? I can't find why?

[MFran.4 · Accepted solution]

It could be the wires but 10cm is still a human distance. Did you measure with an oscilloscope SDA and SCL? Are the waveforms clean?

[ATavo.1]

It seems that one the capacitors was not correctly soldered and it change the ground. it works for now.

Thnx everyone.