STM8S001J3 I2C: Nothing happens

[maximilian]

Posted on September 11, 2017 at 15:06

I'm trying to get I2C to work, but nothing happens on either SDA nor SCL.

I've connected the STM8S001J3 like so:

Pin 5 SDA

Pin 6 SCL

(There are pull-ups on both of the lines)

1. I initialize the clocks:

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_HSIDIV8);
CLK_SYSCLKConfig(CLK_PRESCALER_CPUDIV2);
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);�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?

Then I set the pins:

/*SDA, SCL*/
GPIO_Init(GPIOB, GPIO_PIN_4, GPIO_MODE_OUT_OD_HIZ_FAST);
GPIO_Init(GPIOB, GPIO_PIN_5, GPIO_MODE_OUT_OD_HIZ_FAST);�?�?�?

Inititalize I2C:

void Init_I2C1(uint32_t clockSpeed, uint8_t ownAddress)
{
I2C_Cmd(DISABLE);
I2C_Init(clockSpeed,
ownAddress,
I2C_DUTYCYCLE_2,
I2C_ACK_CURR, 
 I2C_ADDMODE_7BIT,
16
);
I2C_Cmd(ENABLE);
}
�?�?�?�?�?�?�?�?�?�?�?�?

And then I (try to) write:

DS442x_ReturnState returnState = { .state = (uint8_t)1 };
uint16_t timeout = DAC_DS442x_Timeout;
I2C_GenerateSTART(ENABLE);
while(!I2C_GetFlagStatus(I2C_FLAG_STARTDETECTION))
{
timeout--;
if(timeout == 0)
{
returnState.state = 0;
return returnState;
}
}
I2C->DR = (uint8_t)(address << 1);
timeout = DAC_DS442x_Timeout;
while(!I2C_GetFlagStatus(I2C_FLAG_ADDRESSSENTMATCHED))
{
timeout--;
if(timeout == 0)
{
returnState.state = 0;
return returnState;
}
}
I2C_ClearFlag(I2C_FLAG_ADDRESSSENTMATCHED);
timeout = DAC_DS442x_Timeout;
while(!I2C_GetFlagStatus(I2C_FLAG_TXEMPTY))
{
timeout--;
if(timeout == 0)
{
returnState.state = 0;
return returnState;
}
}
I2C->DR = registerAddress;
timeout = DAC_DS442x_Timeout;
while(!I2C_GetFlagStatus(I2C_FLAG_TXEMPTY))
{
timeout--;
if(timeout == 0)
{
returnState.state = 0;
return returnState;
}
}
I2C->DR = data;
timeout = DAC_DS442x_Timeout;
while(!I2C_GetFlagStatus(I2C_FLAG_TRANSFERFINISHED))
{
timeout--;
if(timeout == 0)
{
returnState.state = 0;
return returnState;
}
}
I2C_GenerateSTOP(ENABLE);
return returnState;�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?

But nothing happens - as in, there are no signals on the lines.

Am I missing something?

Thanks in advance!

#i2c #stm8s