application note AN3281 to implement the I2C bus for the STM8S microcontroller.

[PhilippeSIMIER]

You have published an application note AN3281 to implement the I2C bus.

Where can we download the example programs described in the note?

Thank you for your answers

[Peter BENSCH]

You can find it on the website of the STSW-STM8004.

Good luck!

Regards

/Peter

[PhilippeSIMIER]

Thanks

[Peter BENSCH]

You're welcome!

If the problem is solved, please mark this thread as answered by selecting Select as best, as also explained here. This will help other users find that answer faster.

Regards

/Peter

[PhilippeSIMIER]

I managed to download the program. Thanks.

Have you released an equivalent that uses the SPL library?

Regards

[Peter BENSCH]

The program for the AN3281 was developed many years before the SPL and represents, so to speak, a first approach to working with I2C on the STM8.

However, the SPL has since supported all functions of the I2C peripheral in the STM8, so the AN3281 should only be considered as a reference.

Regards

/Peter

[PhilippeSIMIER]

My issue is the following :

I use the nucleo_8s207k8 evaluation kit.

I am trying to enable I2C bus as master with these functions

void clock_setup(void) {
 
    CLK_DeInit();
 
    CLK_HSECmd(DISABLE);
    CLK_LSICmd(DISABLE);
    CLK_HSICmd(ENABLE);
    while (CLK_GetFlagStatus(CLK_FLAG_HSIRDY) == FALSE);
 
 
    CLK_ClockSwitchCmd(ENABLE);
    CLK_HSIPrescalerConfig(CLK_PRESCALER_HSIDIV1); // HSI à 16 MHz
    CLK_SYSCLKConfig(CLK_PRESCALER_CPUDIV1);  // soit CPU à 16Mhz
 
    CLK_ClockSwitchConfig(CLK_SWITCHMODE_AUTO, CLK_SOURCE_HSI,
            DISABLE, CLK_CURRENTCLOCKSTATE_ENABLE);
 
    CLK_PeripheralClockConfig(CLK_PERIPHERAL_SPI, DISABLE);
    CLK_PeripheralClockConfig(CLK_PERIPHERAL_I2C, ENABLE);
    CLK_PeripheralClockConfig(CLK_PERIPHERAL_ADC, DISABLE);
    CLK_PeripheralClockConfig(CLK_PERIPHERAL_AWU, DISABLE);
    CLK_PeripheralClockConfig(CLK_PERIPHERAL_UART1, DISABLE);
    CLK_PeripheralClockConfig(CLK_PERIPHERAL_TIMER1, DISABLE);
    CLK_PeripheralClockConfig(CLK_PERIPHERAL_TIMER2, DISABLE);
    CLK_PeripheralClockConfig(CLK_PERIPHERAL_TIMER4, DISABLE);
}
 
void GPIO_setup(void) {
    GPIO_DeInit(GPIOB);
    GPIO_Init(GPIOB, GPIO_PIN_4, GPIO_MODE_OUT_OD_HIZ_FAST);
    GPIO_Init(GPIOB, GPIO_PIN_5, GPIO_MODE_OUT_OD_HIZ_FAST);
    GPIO_WriteHigh(GPIOB, GPIO_PIN_4);
    GPIO_WriteHigh(GPIOB, GPIO_PIN_5);
}
 
void I2C_setup(void) {
    I2C_DeInit();
    I2C_Init(10000,
            BH1750_addr,
            I2C_DUTYCYCLE_2,
            I2C_ACK_CURR,
            I2C_ADDMODE_7BIT,
            16);
    
    I2C_Cmd(ENABLE);
}

However the I2C_FLAG_BUSBUSY remains at logical true

Why ?

    uint16_t time_out = 5000;
 
    /* If I2C bus is busy wait until it is free */
    while (I2C_GetFlagStatus(I2C_FLAG_BUSBUSY)&& (--time_out));
    if (!time_out) return 1;

Do you have an explanation ?

regards

Philippe S Teacher