ADC 1 STM8S Discovery, speed is very slow. I am getting the speed as 1.152 milli seconds per sample, can you please tell me what is wrong with my code, I have attached the snapshot of code below.

[Pradeep K]

Posted on July 17, 2017 at 11:06

I want to read the ADC sample value connected to Port B pin 0, when I check the sampling speed, I get it as 1.152 milli seconds per sample, can you let me know if my setting are correct. I am not using timer1 in my code.

//Clock Configuration

static void CLK_Config(void)

{ CLK_HSIPrescalerConfig(CLK_PRESCALER_HSIDIV1); return;}

//ADC configuration

static void ADC_Config( void )

{ ADC1_DeInit();ADC1_Init(ADC1_CONVERSIONMODE_CONTINUOUS, ADC1_CHANNEL_0, ADC1_PRESSEL_FCPU_D2, ADC1_EXTTRIG_TIM,DISABLE, ADC1_ALIGN_RIGHT, ADC1_SCHMITTTRIG_CHANNEL0, DISABLE );

ADC1_ITConfig(ADC1_IT_EOCIE, ENABLE);

ADC1_StartConversion();

return;

}

//GPIO Configuration

GPIO_Init(GPIOB, GPIO_PIN_0, GPIO_MODE_IN_FL_NO_IT);

GPIO_Init(GPIOB, GPIO_PIN_1, GPIO_MODE_OUT_PP_LOW_FAST);

//ADC ISR 22

void ADC1_Sample_IRQHandler(void)

{ PeakHold = ADC1_GetConversionValue(); ADC1_ClearITPendingBit(ADC1_IT_EOCIE); ADC1_ClearFlag(ADC1_IT_EOC); ADC1->CR1 |= ADC1_CR1_CONT; GPIO_WriteReverse(GPIOB, GPIO_PIN_1);}

when I monitor the pin 1 in oscilloscope, I see the signal is changing it's state every 1.152 msecond. But the manual says the ADC speed is 2.33 micro second. Can I know what is the mistake in my configuration.