本文主要是介绍STM32 ADC多通道规则采样和注入采样,希望对大家解决编程问题提供一定的参考价值,需要的开发者们随着小编来一起学习吧!
layout: post
tags: [STM32]
comments: true
文章目录
- layout: post tags: [STM32] comments: true
- 什么是ADC?
- STM32 ADC的特性
- 采样模式
- 采样时间
- 代码实现
什么是ADC?
Analog to Digital Converter
,将模拟信号转换成数字的模数转换器,后面可能还会接触到DAC
,恰恰相反,是将数字信号转换成模拟信号。具体的原理可以自行找搜索引擎,可以得到更好的答案。
STM32 ADC的特性
参考手册给出ADC的功能十分丰富,具体如下:
12 bit
分辨率,量化到0-4096
的范围;- 转换结束、注入转换结束和发生模拟看门狗事件时产生中断
- 单次和连续转换模式
- 从通道0到通道n的自动扫描模式
- 自校准
- 带内嵌数据一致性的数据对齐
- 采样间隔可以按通道分别编程
- 规则转换和注入转换均有外部触发选项
- 间断模式
本文只讨论规则采样和注入采样,并给出具体的代码实现,更多细节还需要参考《STM32参考手册》
采样模式
- 规则采样:相当于软件触发采样,可以在程序里主动调用规则采样去读取具体的
ADC
值,同样 - 注入采样:相当于中断,所以需要具体的触发源,比如外部的信号可以触发注入采样,
ADC
转换成功之后,便会触发ADC
中断,在中断服务子程序中,就可以读取ADC
值;
触发源可以是外部信号,也可以是定时器的触发信号;标准库中注入模式的触发信号如下所示;
注入组的外部触发信号
/** @defgroup ADC_external_trigger_sources_for_injected_channels_conversion * @{*/#define ADC_ExternalTrigInjecConv_T2_TRGO ((uint32_t)0x00002000) /*!< For ADC1 and ADC2 */
#define ADC_ExternalTrigInjecConv_T2_CC1 ((uint32_t)0x00003000) /*!< For ADC1 and ADC2 */
#define ADC_ExternalTrigInjecConv_T3_CC4 ((uint32_t)0x00004000) /*!< For ADC1 and ADC2 */
#define ADC_ExternalTrigInjecConv_T4_TRGO ((uint32_t)0x00005000) /*!< For ADC1 and ADC2 */
#define ADC_ExternalTrigInjecConv_Ext_IT15_TIM8_CC4 ((uint32_t)0x00006000) /*!< For ADC1 and ADC2 */#define ADC_ExternalTrigInjecConv_T1_TRGO ((uint32_t)0x00000000) /*!< For ADC1, ADC2 and ADC3 */
#define ADC_ExternalTrigInjecConv_T1_CC4 ((uint32_t)0x00001000) /*!< For ADC1, ADC2 and ADC3 */
#define ADC_ExternalTrigInjecConv_None ((uint32_t)0x00007000) /*!< For ADC1, ADC2 and ADC3 */#define ADC_ExternalTrigInjecConv_T4_CC3 ((uint32_t)0x00002000) /*!< For ADC3 only */
#define ADC_ExternalTrigInjecConv_T8_CC2 ((uint32_t)0x00003000) /*!< For ADC3 only */
#define ADC_ExternalTrigInjecConv_T8_CC4 ((uint32_t)0x00004000) /*!< For ADC3 only */
#define ADC_ExternalTrigInjecConv_T5_TRGO ((uint32_t)0x00005000) /*!< For ADC3 only */
#define ADC_ExternalTrigInjecConv_T5_CC4 ((uint32_t)0x00006000) /*!< For ADC3 only */
规则组的外部触发信号
#define ADC_ExternalTrigConv_T1_CC1 ((uint32_t)0x00000000) /*!< For ADC1 and ADC2 */
#define ADC_ExternalTrigConv_T1_CC2 ((uint32_t)0x00020000) /*!< For ADC1 and ADC2 */
#define ADC_ExternalTrigConv_T2_CC2 ((uint32_t)0x00060000) /*!< For ADC1 and ADC2 */
#define ADC_ExternalTrigConv_T3_TRGO ((uint32_t)0x00080000) /*!< For ADC1 and ADC2 */
#define ADC_ExternalTrigConv_T4_CC4 ((uint32_t)0x000A0000) /*!< For ADC1 and ADC2 */
#define ADC_ExternalTrigConv_Ext_IT11_TIM8_TRGO ((uint32_t)0x000C0000) /*!< For ADC1 and ADC2 */#define ADC_ExternalTrigConv_T1_CC3 ((uint32_t)0x00040000) /*!< For ADC1, ADC2 and ADC3 */
#define ADC_ExternalTrigConv_None ((uint32_t)0x000E0000) /*!< For ADC1, ADC2 and ADC3 */#define ADC_ExternalTrigConv_T3_CC1 ((uint32_t)0x00000000) /*!< For ADC3 only */
#define ADC_ExternalTrigConv_T2_CC3 ((uint32_t)0x00020000) /*!< For ADC3 only */
#define ADC_ExternalTrigConv_T8_CC1 ((uint32_t)0x00060000) /*!< For ADC3 only */
#define ADC_ExternalTrigConv_T8_TRGO ((uint32_t)0x00080000) /*!< For ADC3 only */
#define ADC_ExternalTrigConv_T5_CC1 ((uint32_t)0x000A0000) /*!< For ADC3 only */
#define ADC_ExternalTrigConv_T5_CC3 ((uint32_t)0x000C0000) /*!< For ADC3 only */
从参考手册中可以看到ADC
的框架,注入通道转换成功之后,标志位JEOC
使能,然后JEOCIE
中断位被使能,最终触发ADC中断;
采样时间
标准库中对于采样周期的定义;
#define ADC_SampleTime_1Cycles5 ((uint8_t)0x00)
#define ADC_SampleTime_7Cycles5 ((uint8_t)0x01)
#define ADC_SampleTime_13Cycles5 ((uint8_t)0x02)
#define ADC_SampleTime_28Cycles5 ((uint8_t)0x03)
#define ADC_SampleTime_41Cycles5 ((uint8_t)0x04)
#define ADC_SampleTime_55Cycles5 ((uint8_t)0x05)
#define ADC_SampleTime_71Cycles5 ((uint8_t)0x06)
#define ADC_SampleTime_239Cycles5 ((uint8_t)0x07)
TCONV = 采样时间+ 12.5个周期
ADC_InjectedChannelConfig(ADC1, ADC_Channel_0, 1, ADC_SampleTime_1Cycles5);
当ADCCLK=14MHz
,采样时间为1.5周期(ADC_SampleTime_1Cycles5
)
采样时间:TCONV = 1.5 + 12.5 = 14周期 = 1μs
代码实现
基于ST
标准库V3.5
,实现了ADC
规则采样和注入采样两种模式;
current.h
#ifndef CURRENT_H
#define CURRENT_H
#include <stdint.h>#define RES_IA 1024 //采样电阻A
#define RES_IB 1024 //采样电阻B/*** Ia--->PA0/ADC0* |------------>PA2/ADC2* Ib--->PA1/ADC1* |------------>PA3/ADC3*/void cur_fbk_init(void);uint16_t cur_fbk_get_Ia(void);
uint16_t cur_fbk_get_Ia_avl(uint8_t sample_times);
uint16_t cur_fbk_get_Ib(void);
uint16_t cur_fbk_get_Ib_avl(uint8_t sample_times);uint16_t get_inject_ia(void);
uint16_t get_inject_ib(void);int16_t cur_fbk_get_theta(void);#endif
current.c
#include "current.h"
#include "stm32f10x.h"
#include "stm32f10x_gpio.h"
#include "stm32f10x_adc.h"
#include "stm32f10x_rcc.h"
#include <stdint.h>#if 1
#define IA_CHANNEL_DRI ADC_Channel_0
#define IB_CHANNEL_DRI ADC_Channel_1
#else
#define IA_CHANNEL_DRI ADC_Channel_2
#define IB_CHANNEL_DRI ADC_Channel_3
#endifvolatile uint16_t Ia_val = 0;
volatile uint16_t Ib_val = 0;static void cur_fbk_irq_init(void){NVIC_InitTypeDef NVIC_InitStructure;/* Configure and enable ADC interrupt */NVIC_InitStructure.NVIC_IRQChannel = ADC1_2_IRQn;NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0;NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0;NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;NVIC_Init(&NVIC_InitStructure);}static void cur_fbk_adc_init(void){ADC_DeInit(ADC1);ADC_InitTypeDef ADC_InitStructure;/* ADC1 configuration ------------------------------------------------------*/ADC_InitStructure.ADC_Mode = ADC_Mode_Independent;ADC_InitStructure.ADC_ScanConvMode = ENABLE;ADC_InitStructure.ADC_ContinuousConvMode = DISABLE;ADC_InitStructure.ADC_ExternalTrigConv = ADC_ExternalTrigConv_T1_CC1;ADC_InitStructure.ADC_DataAlign = ADC_DataAlign_Right;ADC_InitStructure.ADC_NbrOfChannel = 2;/* Set injected sequencer length */ADC_InjectedSequencerLengthConfig(ADC1, 2);/* ADC1 injected channel Configuration */ ADC_InjectedChannelConfig(ADC1, ADC_Channel_0, 1, ADC_SampleTime_71Cycles5);ADC_InjectedChannelConfig(ADC1, ADC_Channel_1, 2, ADC_SampleTime_71Cycles5);//ADC_InjectedChannelConfig(ADC1, ADC_Channel_2, 1, ADC_SampleTime_71Cycles5);//ADC_InjectedChannelConfig(ADC1, ADC_Channel_3, 1, ADC_SampleTime_71Cycles5); /* ADC1 injected external trigger configuration *///ADC_ExternalTrigInjectedConvConfig(ADC1, ADC_ExternalTrigInjecConv_T1_CC4);ADC_ExternalTrigInjectedConvConfig(ADC1, ADC_ExternalTrigInjecConv_None);//ADC_SetInjectedOffset(ADC1, ADC_InjectedChannel_1,2048);//ADC_SetInjectedOffset(ADC1, ADC_InjectedChannel_2,2048);/* Enable automatic injected conversion start after regular one */ADC_AutoInjectedConvCmd(ADC1, ENABLE);/* Enable ADC1 DMA */ADC_DMACmd(ADC1, ENABLE);/* Enable ADC1 external trigger */ ADC_ExternalTrigConvCmd(ADC1, ENABLE);ADC_Init(ADC1, &ADC_InitStructure);ADC_Cmd(ADC1, ENABLE);ADC_ResetCalibration(ADC1);while(ADC_GetResetCalibrationStatus(ADC1)){/**TODOtimeout_detect*/}ADC_StartCalibration(ADC1);while(ADC_GetCalibrationStatus(ADC1)){/**TODOtimeout_detect*/}ADC_ITConfig(ADC1, ADC_IT_JEOC, ENABLE);
}static void cur_fbk_rcc_init(void){/* ADCCLK = PCLK2/6 */RCC_ADCCLKConfig(RCC_PCLK2_Div6); /* Enable peripheral clocks ------------------------------------------------*//* Enable DMA1 and DMA2 clocks *///RCC_AHBPeriphClockCmd(RCC_AHBPeriph_DMA1 | RCC_AHBPeriph_DMA2, ENABLE);/* Enable ADC1 and GPIOA clocks */RCC_APB2PeriphClockCmd(RCC_APB2Periph_ADC1 | RCC_APB2Periph_GPIOA, ENABLE);
}static void cur_fbk_pin_init(void){GPIO_InitTypeDef GPIO_InitStructure;GPIO_InitStructure.GPIO_Pin = GPIO_Pin_0 | GPIO_Pin_1 | GPIO_Pin_2 | GPIO_Pin_3;GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AIN;GPIO_Init(GPIOA, &GPIO_InitStructure); }static uint16_t cur_fbk_get_ad_val(uint8_t channel){ADC_RegularChannelConfig(ADC1, channel, 1, ADC_SampleTime_239Cycles5 );ADC_SoftwareStartConvCmd(ADC1, ENABLE); //使能软件转换功能//等待转换结束/*EOC:转换结束位 (End of conversion)该位由硬件在(规则或注入)通道组转换结束时设置,由软件清除或由读取ADC_DR时清除0:转换未完成;1:转换完成。 */while((ADC1->SR & ADC_FLAG_EOC) != ADC_FLAG_EOC){}//while(!ADC_GetFlagStatus(ADC1, ADC_FLAG_EOC )){}return ADC_GetConversionValue(ADC1); //返回最近一次 ADC1 规则组的转换结果
}void cur_fbk_init(void){cur_fbk_rcc_init();cur_fbk_pin_init();cur_fbk_irq_init();cur_fbk_adc_init();
}uint16_t cur_fbk_get_Ia_avl(uint8_t sample_times){uint32_t Ia_sum = 0;int8_t i;for(; i < sample_times; i++){Ia_sum+=cur_fbk_get_Ia();}return (uint16_t)(Ia_sum/sample_times);
}uint16_t cur_fbk_get_Ib_avl(uint8_t sample_times){uint32_t Ib_sum = 0;int8_t i = 0;for(;i < sample_times; i++){Ib_sum+=cur_fbk_get_Ib();}return (uint16_t)(Ib_sum/sample_times);
}uint16_t cur_fbk_get_Ia(void){return cur_fbk_get_ad_val(IA_CHANNEL_DRI);
}uint16_t cur_fbk_get_Ib(void){return cur_fbk_get_ad_val(IB_CHANNEL_DRI);
}int16_t cur_fbk_get_theta(void){return 0;
}/******************************************************************************/
/* STM32F10x Peripherals Interrupt Handlers */
/******************************************************************************//*** @brief This function handles ADC1 and ADC2 global interrupts requests.* @param None* @retval None*/
void ADC1_2_IRQHandler(void)
{Ia_val = ADC_GetInjectedConversionValue(ADC1, ADC_InjectedChannel_1);Ib_val = ADC_GetInjectedConversionValue(ADC1, ADC_InjectedChannel_2);/* Clear ADC1 JEOC pending interrupt bit */ADC_ClearITPendingBit(ADC1, ADC_IT_JEOC);
}uint16_t get_inject_ia(void){return Ia_val;
}uint16_t get_inject_ib(void){return Ib_val;
}
这篇关于STM32 ADC多通道规则采样和注入采样的文章就介绍到这儿,希望我们推荐的文章对编程师们有所帮助!