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STM32F102C8T I2C, GPIOB set up properly but GPIO never gets in START (drain) condition

Question asked by klopcic.vid on Aug 5, 2016
Latest reply on Aug 5, 2016 by waclawek.jan
I have a problem regarding I2C comm on STM32F102. I am using CubeMX to generate init code. Every time I try to transmit as master it successfully sets START bit in CR1, and waits until SB in SR1 is sets to 1 (which is) and executes:

/* Send slave address */
hi2c->Instance->DR = I2C_7BIT_ADD_WRITE(DevAddress);

Then nothing happens on GPIO - line remains HIGH and it returns HAL_TIMEOUT in

/* Wait until ADDR flag is set */


  if(I2C_WaitOnMasterAddressFlagUntilTimeout(hi2c, I2C_FLAG_ADDR, Timeout) != HAL_OK)

If you look at I2C->SR1 ARLO (arbitration lost) is set. I have no idea what else could I check to get the bus working. The same code works on nucleo L053R8 board (which is connected to the same line - so pullups and everything else is OK).

You can take a look at entire configuration - CUBE pins, CUBE "configuration", and registers of MCU after hi2c->Instance->DR = I2C_7BIT_ADD_WRITE(DevAddress); command: google photos album

Thanks for your help!