STM32F030C8 I2C1 in BUS_BUSY after first start pulse.

Wanderer · ‎2020-02-04

First I thouht that problem in code generation from Cube, rewrote all in CMSIS, but nothing changed.

I2C using only as a "slave", but after generation "start" and sending addres (0x70) + write no interrupt flags is set. Where my mistake?

Initialisation code here:

RCC->AHBENR|=RCC_AHBENR_GPIOBEN;

GPIOB->MODER|=GPIO_MODER_MODER6_1|GPIO_MODER_MODER7_1;

GPIOB->OSPEEDR|=GPIO_OSPEEDR_OSPEEDR6_0|GPIO_OSPEEDR_OSPEEDR7_0;

GPIOB->AFR[0]|=0x11000000;

RCC->APB1ENR|=RCC_APB1ENR_I2C1EN;

I2C1->CR1|=I2C_CR1_PE;

I2C1->CR1&=~I2C_CR1_PE;

|I2C_CR1_ADDRIE;

I2C1->CR2|=I2C_CR2_NACK;

I2C1->OAR1|=I2C_OAR1_OA1EN;

I2C1->OAR1|=(0x70<<1);

I2C1->TIMINGR=0x00200000;

I2C1->CR1|=I2C_CR1_PE;

__enable_irq ();

HAL_NVIC_EnableIRQ(I2C1_IRQn);

Thank you for help.

KnarfB · ‎2020-02-04

I don't really get your point. A I2C slave will not send its address. It may only respond to a master read/write request.

for HAL I2C slave sample code look at my comment in "Connecting Raspberry PI to STM32F105xx via I2C". (Does the forum have permanent links for that?).

hth

KnarfB