STM32 ADC single channel single routine

#include "stm32f10x.h"

/*RCC clock configuration*/

void RCC_config(void)

{ 

 ErrorStatus HSEStartUpStatus;

 /* RCC registers are set to default configuration */

 RCC_DeInit();

 /* Turn on external high speed clock */

 RCC_HSEConfig(RCC_HSE_ON);

 /* Wait for the external high-speed clock to stabilize*/

 HSEStartUpStatus = RCC_WaitForHSEStartUp();

 if(HSEStartUpStatus == SUCCESS) 

 { 

  /* Set HCLK = SYSCLK */

  RCC_HCLKConfig(RCC_SYSCLK_Div1);

  /* Set PCLK2 = HCLK */

  RCC_PCLK2Config(RCC_HCLK_Div1);

  /* Set PCLK1 = HCLK / 2 */

  RCC_PCLK1Config(RCC_HCLK_Div2);

// /* Set FLASH code delay */

//  FLASH_SetLatency(FLASH_Latency_2);

// /* Enable prefetch cache */

//  FLASH_PrefetchBufferCmd(FLASH_PrefetchBuffer_Enable);

  /* Set the PLL clock source to HSE multiplier 9 72MHz */

  RCC_PLLConfig(RCC_PLLSource_HSE_Div1, RCC_PLLMul_9);

  /* Enable PLL */

  RCC_PLLCmd(ENABLE);

  /* Wait for PLL to stabilize */

  while(RCC_GetFlagStatus(RCC_FLAG_PLLRDY) == RESET);

  /* Set PLL as system clock source */

  RCC_SYSCLKConfig(RCC_SYSCLKSource_PLLCLK);

  /* Wait for the system clock source to switch to PLL */

  while(RCC_GetSYSCLKSource() != 0x08);

 }

}

/* Millisecond delay function */

void delay_ms(uint16_t time)

{    

 uint16_t i = 0; 

 while(time--)

 {

  i = 12000;

  while(i--);    

 }

}

/* GPIO configuration */

void GPIO_config(void)

{

 GPIO_InitTypeDef GPIO_InitStructure;

 /* Clock configuration */

 RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOB, ENABLE);

 /* Analog input */

 GPIO_InitStructure.GPIO_Pin = GPIO_Pin_0;

 GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AIN;

 GPIO_Init(GPIOA, &GPIO_InitStructure);

}

/* ADC configuration */

void ADC_config(void)

{

 ADC_InitTypeDef ADC_InitStructure;

 /* Enable clock */

 RCC_APB2PeriphClockCmd(RCC_APB2Periph_ADC1, ENABLE);

 /* Configure ADC clock 12MHz */

 RCC_ADCCLKConfig(RCC_PCLK2_Div6);

 ADC_InitStructure.ADC_Mode = ADC_Mode_Independent; /* Independent mode*/

 ADC_InitStructure.ADC_ScanConvMode = DISABLE; /* Single channel mode*/

 ADC_InitStructure.ADC_ContinuousConvMode = DISABLE; /* Single conversion mode*/

 ADC_InitStructure.ADC_ExternalTrigConv = ADC_ExternalTrigConv_None; /* Software trigger*/

 ADC_InitStructure.ADC_DataAlign = ADC_DataAlign_Right; /* Data right aligned*/

 ADC_InitStructure.ADC_NbrOfChannel = 1; /* 1 channel */

 ADC_Init(ADC1, &ADC_InitStructure);

 /* Analog channel 0, sampling sequence 1, sampling period 55.5 */

 ADC_RegularChannelConfig(ADC1, ADC_Channel_0, 1, ADC_SampleTime_55Cycles5);

 /* Enable ADC */

 ADC_Cmd(ADC1, ENABLE);

 /* Reset calibration registers */

 ADC_ResetCalibration(ADC1);

 while(ADC_GetResetCalibrationStatus(ADC1));

 /* Start calibration */

 ADC_StartCalibration(ADC1);

 while(ADC_GetCalibrationStatus(ADC1));

}

/* Main function */

int main(void)

{

 uint32_t value;

 volatile float V;

 /*RCC clock configuration*/

 RCC_config();

 /* IO placement */

 GPIO_config();

 /* ADC configuration */

 ADC_config();

 while(1)

 {

  /* Start conversion */

  ADC_SoftwareStartConvCmd(ADC1, ENABLE);

  /* Wait for the conversion to finish */

  while(!ADC_GetFlagStatus(ADC1, ADC_FLAG_EOC));

  /* Get the conversion value */

  value = ADC_GetConversionValue(ADC1);

  /* Convert digital quantity to voltage value*/

  V = (float)value / 4096 * 3.3;

  delay_ms(1000);

 }

}