1. 前言

本教程基于【N32WB03x SDK使用指南】的开发环境，结合官方教程开展的N32WB03xSTB开发板ADC实验，主要由读取两路ADC并打印实验和读取板载芯片温度实验两部分组成。

2. ADC 功能描述

2.1 输入通道和输入电压范围

ADC 是一种高速逐次逼近型模拟数字转换器。有多达 8 个通道，5 个外部单端，1 个差分 MIC 和 2 个内部通道。内部通道包括 VCC 检测通道和温度传感器通道。各通道的 A/D 转换可以单次、连续模式执行。配置 ADC_CTRL.ADC_CH_SEL 用于 ADC 输入通道选择。

000（默认）选择差分 MIC 通路，对应 PB11/PB13，
001～010 用于片外预分压输入，对应
PB9/PB10，无阻性负载，检测范围 0.125～0.85V，
011～101 用于直接检测，对应 PB6~PB8，输入阻抗360KΩ，检测范围 0.5～3.5V，
110 用于 VCC 检测，
111 用于片内温度传感器电压检测。

2.2 ADC 开关控制

通过设置 ADC_CTRL 寄存器的 ADC_EN 位可启动 ADC。当第一次设置 ADC_EN 位时，ADC 在开始精确转换前需要一个稳定时间 tSTAB 64 cycle。之后每个 Cycle 进行一次转换。在单次模式下，转换完成后，硬件自动关闭 ADC_EN 位。如使能中断，可产生转换结束中断。用户可以通过查询 ADC_SR 里面的 ADC_DONE_F 确认转换是否完成。在连续模式下，通过清除 ADC_EN 位可以停止转换。输入通道切换前需要先关闭 ADC_EN 位。

2.3 转换模式

2.3.1 单次转换模式

每个转换有两个阶段：采样阶段和转换阶段。
单次转换模式下，ADC 只执行一次转换。设置 ADC_CTRL.ADC_CH_SEL 选择输入通道后，可通过设置ADC_CTRL 寄存器的 ADC_EN 位启动。一旦选择通道的转换完成：

•  转换数据被储存在 16 位 ADC_DAT 寄存器中
•  ADC_DONE_F（转换结束）标志被设置
•  如果设置了ADC_DONE_IE，则产生中断。

转换本身很快，只需要一个 adcclk 的时钟周期。但单次模式下，ADCEN 或 ADCSEL 修改后，输入通道的切换电路需要 64 个adcclk 稳定时间。

2.3.2 连续转换模式

将 ADC_CTRL.ADC_MODE 置为“1”可以在连续模式下使用 ADC，在连续转换模式中，当前面 ADC 转
换一结束马上就启动另一次转换。设置 ADC_CTRL.ADC_CH_SEL 选择输入通道后，可通过设置ADC_CTRL 寄存器的 ADC_EN 位来触发第一次转换，但之后，将每个 adcclk 周期自动生成新的转换数据。支持过采样率设置，配置值 ADC_OVR_SAMP_CNT. OS_CNT_LD_CNT 需要>=2，OS_CNT_LD_CNT+1个数据采样一个数据。
每个转换后：

•  转换数据被储存在 16 位的 ADC_DAT 寄存器中
•  使能 DMA 模式，每次转换后会产生 DMA 请求

2.4 模拟看门狗

如果被 ADC 转换的模拟 PB10 电压低于低阈值或高于高阈值，AWDG 模拟看门狗状态位被设置。阈值位于ADC_ WDHIGH 和 ADC_WDLOW 寄存器的最低 10 个有效位中。通过设置 ADC_CTRL 寄存器的 AWD_IE位以允许产生相应中断。

3. ADC 实验

3.1 两路ADC并打印实验

项目文件地址：N32WB03x_SDK V1.2.0\N32WB03x_SDK V1.2.0\projects\n32wb03x_EVAL\peripheral\ADC\ADC_SingleRead\MDK-ARM

3.1.1 打开工程

keil5 打开后查看相关程序函数

项目简介在readme.txt

1、功能说明

	此例程提供了ADC单次转换的实现。
        
2、使用环境

    软件开发环境：KEIL MDK-ARM V5.26.2.0
    
    硬件环境：
        1、基于N32WB031_STB开发板
        2、MCU：N32WB031

3、使用说明 
    
    1、系统时钟：64MHz
    2、ADC通道：ADC_CTRL_CH_1(PB10)、ADC_CTRL_CH_3(PB8)

    
    日志打印：从模式 DEMO 板 PB6(TX)，波特率：115200
    
    测试步骤与现象：
        a，编译下载代码复位运行
        b，从串口看打印信息，验证结果两个通道ADC转换的电压
        
4、注意事项
    开发板的J15 短接右边，J16 短接左边，选择 IO 连接到排针。

3.1.2 配置工程

主程序main.c

/*****************************************************************************
 * Copyright (c) 2019, Nations Technologies Inc.
 *
 * All rights reserved.
 * ****************************************************************************
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 * - Redistributions of source code must retain the above copyright notice,
 * this list of conditions and the disclaimer below.
 *
 * Nations' name may not be used to endorse or promote products derived from
 * this software without specific prior written permission.
 *
 * DISCLAIMER: THIS SOFTWARE IS PROVIDED BY NATIONS "AS IS" AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT ARE
 * DISCLAIMED. IN NO EVENT SHALL NATIONS BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA,
 * OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
 * EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 * ****************************************************************************/

/**
 * [url=home.php?mod=space&uid=1455510]@file[/url] main.c
 * [url=home.php?mod=space&uid=40524]@author[/url] Nations Firmware Team
 * [url=home.php?mod=space&uid=644434]@version[/url] v1.0.2
 *
 * [url=home.php?mod=space&uid=855824]@copyright[/url] Copyright (c) 2019, Nations Technologies Inc. All rights reserved.
 */
#include "main.h"
#include "log.h"

void RCC_Configuration(void);
void GPIO_Configuration(void);
void ADC_Configuration(void);

uint16_t ADCConvertedValue[2];
uint32_t voltage[2] = {0}; 
/**
 * [url=home.php?mod=space&uid=2666770]@Brief[/url]  Main program
 */
int main(void)
{
	log_init();
    log_info("\nthis is adc single read Demo.\n");
	log_info("Please make sure J15 and J16 connect the IO to pin on board!\n");
	/* System Clocks Configuration */
	RCC_Configuration();
	
	/* Configure the GPIO ports */
    GPIO_Configuration();
	
	ADC_EnableBypassFilter(ADC, ENABLE);
    while (1)
    {
		ADC_ConfigChannel(ADC, ADC_CTRL_CH_3);
		ADC_Enable(ADC, ENABLE);
		while(ADC_GetFlagStatus(ADC,ADC_FLAG_DONE) == RESET);
		ADC_ClearFlag(ADC,ADC_FLAG_DONE);  
		ADCConvertedValue[1] = ADC_GetDat(ADC);
    
		voltage[1] = ADC_ConverValueToVoltage(ADCConvertedValue[1], ADC_CTRL_CH_3);
		log_info("ADC CH3 value: %4d  |  ADC CH3 vol_mV: %4d .\r\n",ADCConvertedValue[1],voltage[1]);  
	
		ADC_ConfigChannel(ADC, ADC_CTRL_CH_1);
		ADC_Enable(ADC, ENABLE);
		while(ADC_GetFlagStatus(ADC,ADC_FLAG_DONE) == RESET);
		ADC_ClearFlag(ADC,ADC_FLAG_DONE);  
		ADCConvertedValue[0] = ADC_GetDat(ADC);

		voltage[0] = ADC_ConverValueToVoltage(ADCConvertedValue[0], ADC_CTRL_CH_1);
		log_info("ADC CH1 value: %4d  |  ADC CH1 vol_mV: %4d .\r\n\r\n",ADCConvertedValue[0],voltage[0]);    
		Delay_ms(1000);
    }
}


/**
 * @brief  Configures the different system clocks.
 */
void RCC_Configuration(void)
{
	/* Enable peripheral clocks */
    /* Enable GPIOB clocks */
    RCC_EnableAPB2PeriphClk(RCC_APB2_PERIPH_GPIOB, ENABLE);
    /* Enable ADC clocks */
    RCC_EnableAHBPeriphClk(RCC_AHB_PERIPH_ADC, ENABLE);
        
    RCC_ConfigAdcClk(RCC_ADCCLK_SRC_AUDIOPLL);

    /* enable ADC 4M clock */
    RCC_Enable_ADC_CLK_SRC_AUDIOPLL(ENABLE);
}


/**
 * @brief  Configures the different GPIO ports.
 */
void GPIO_Configuration(void)
{
    GPIO_InitType GPIO_InitStructure;

    GPIO_InitStruct(&GPIO_InitStructure);
    /* Configure PB.10 (ADC Channel1) PB.8 (ADC Channel3) as analog input --------*/
    GPIO_InitStructure.Pin       = GPIO_PIN_10|GPIO_PIN_8;
    GPIO_InitStructure.GPIO_Mode = GPIO_MODE_ANALOG;
    GPIO_InitPeripheral(GPIOB, &GPIO_InitStructure);
}


#ifdef USE_FULL_ASSERT

/**
 * @brief  Reports the name of the source file and the source line number
 *         where the assert_param error has occurred.
 * @param file pointer to the source file name
 * @param line assert_param error line source number
 */
void assert_failed(const uint8_t* expr, const uint8_t* file, uint32_t line)
{
    /* User can add his own implementation to report the file name and line number,
     ex: printf("Wrong parameters value: file %s on line %d\r\n", file, line) */

    while (1)
    {
    }
}

#endif

/**
 * @}
 */

/**
 * @}
 */

/*************** (C) COPYRIGHT Nations Technologies Inc *****END OF FILE***************/

此部分不修改

3.1.3 编译下载

N32WB03xSTB开发板自带下载器，官方已经配置好了，直接连接Type-C编译下载

3.1.4 调试验证

打开串口调试助手，修改相关配置。连接开发板，打印效果如下

此时可以用GND或者3.3V电源用杜邦线短接ADC_CTRL_CH_1(PB10)、ADC_CTRL_CH_3(PB8)
，也会有相关大小变化

[11:38:01.339]收←◆ADC CH3 value:   64  |  ADC CH3 vol_mV:   77 .
ADC CH1 value:  502  |  ADC CH1 vol_mV:  496 .


[11:38:02.373]收←◆ADC CH3 value:   65  |  ADC CH3 vol_mV:   81 .
ADC CH1 value:  527  |  ADC CH1 vol_mV:  523 .


[11:38:03.408]收←◆ADC CH3 value:   64  |  ADC CH3 vol_mV:   77 .
ADC CH1 value:  880  |  ADC CH1 vol_mV:  908 .


[11:38:04.442]收←◆ADC CH3 value:   66  |  ADC CH3 vol_mV:   86 .
ADC CH1 value:  159  |  ADC CH1 vol_mV:  123 .


[11:38:05.477]收←◆ADC CH3 value:   65  |  ADC CH3 vol_mV:   81 .
ADC CH1 value:  750  |  ADC CH1 vol_mV:  767 .


[11:38:06.511]收←◆ADC CH3 value:   59  |  ADC CH3 vol_mV:   55 .
ADC CH1 value:  789  |  ADC CH1 vol_mV:  809 .

3.2 读取板载芯片温度实验

项目文件地址：N32WB03x_SDK V1.2.0\projects\n32wb03x_EVAL\peripheral\ADC\ADC_Temperature\MDK-ARM

3.1.1 打开工程

keil5 打开后查看相关程序函数

项目简介在readme.txt

1、功能说明

	此例程提供了ADC温度传感通道转换的实现。
        
2、使用环境

    软件开发环境：KEIL MDK-ARM V5.26.2.0
    
    硬件环境：
        1、基于N32WB031_STB开发板
        2、MCU：N32WB031

3、使用说明 
    
    1、系统时钟：64MHz
    2、ADC通道：ADC_CTRL_CH_7(TS)

    
    日志打印：从模式 DEMO 板 PB6(TX)，波特率：115200
    
    测试步骤与现象：
        a，编译下载代码复位运行
        b，从串口看打印信息，验证温度传感通道ADC转换的结果
        
4、注意事项
    无

3.1.2 配置工程

主程序main.c

/*****************************************************************************
 * Copyright (c) 2019, Nations Technologies Inc.
 *
 * All rights reserved.
 * ****************************************************************************
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 * - Redistributions of source code must retain the above copyright notice,
 * this list of conditions and the disclaimer below.
 *
 * Nations' name may not be used to endorse or promote products derived from
 * this software without specific prior written permission.
 *
 * DISCLAIMER: THIS SOFTWARE IS PROVIDED BY NATIONS "AS IS" AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT ARE
 * DISCLAIMED. IN NO EVENT SHALL NATIONS BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA,
 * OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
 * EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 * ****************************************************************************/

/**
 * @file main.c
 * @author Nations Firmware Team
 * @version v1.0.2
 *
 * @copyright Copyright (c) 2019, Nations Technologies Inc. All rights reserved.
 */
 
/* Includes ------------------------------------------------------------------*/
#include "main.h"
#include "log.h"
/* Private typedef -----------------------------------------------------------*/
/* Private define ------------------------------------------------------------*/
#define ADC_BUF_SIZE     (10)

/* Private constants ---------------------------------------------------------*/
/* Private variables ---------------------------------------------------------*/
uint16_t ADCConvertedBuffer[ADC_BUF_SIZE];
uint16_t ADCConvertedValue;
uint32_t Voltage_mA; 
float Temperature; 
/* Private function prototypes -----------------------------------------------*/
void RCC_Configuration(void);
void GPIO_Configuration(void);
void ADC_Configuration(void);
/* Private functions ---------------------------------------------------------*/


/**
 * @brief  Main program
 */
int main(void)
{
    DMA_InitType DMA_InitStructure;
    uint32_t adc_sum,i;
    
    log_init();
    log_info("\nthis is adc temperature sensor read demo.\n");
    
    /* System Clocks Configuration */
    RCC_Configuration();
    
    /* Configure the GPIO ports */
    GPIO_Configuration();
    
    /* DMA channel1 configuration ----------------------------------------------*/
    DMA_DeInit(DMA_CH1);
    DMA_InitStructure.PeriphAddr     = (uint32_t)&ADC->DAT;
    DMA_InitStructure.MemAddr        = (uint32_t)ADCConvertedBuffer;
    DMA_InitStructure.Direction      = DMA_DIR_PERIPH_SRC;
    DMA_InitStructure.BufSize        = ADC_BUF_SIZE;
    DMA_InitStructure.PeriphInc      = DMA_PERIPH_INC_DISABLE;
    DMA_InitStructure.DMA_MemoryInc  = DMA_MEM_INC_ENABLE;
    DMA_InitStructure.PeriphDataSize = DMA_PERIPH_DATA_SIZE_HALFWORD;
    DMA_InitStructure.MemDataSize    = DMA_MemoryDataSize_HalfWord;
    DMA_InitStructure.CircularMode   = DMA_MODE_CIRCULAR;
    DMA_InitStructure.Priority       = DMA_PRIORITY_HIGH;
    DMA_InitStructure.Mem2Mem        = DMA_M2M_DISABLE;
    DMA_Init(DMA_CH1, &DMA_InitStructure);
    DMA_RequestRemap(DMA_REMAP_ADC, DMA, DMA_CH1, ENABLE);

    /* Enable DMA channel 1 */
    DMA_EnableChannel(DMA_CH1, ENABLE);
    ADC_SetOverSampleCounter(ADC,3);
    ADC_EnableBypassFilter(ADC, ENABLE);
    ADC_ConfigChannel(ADC, ADC_CTRL_CH_7);
    ADC_ConfigContinuousMode(ADC, ENABLE);
    ADC_EnableDMA(ADC, ENABLE);
    ADC_EnableTS(ADC, ENABLE);
    ADC_Enable(ADC, ENABLE);

    while (1)
    {

        /* Transfer complete */
        while (!DMA_GetFlagStatus(DMA_FLAG_TC1, DMA));
        adc_sum = 0;
        for(i=0;i<ADC_BUF_SIZE;i++)
        {
            adc_sum += ADCConvertedBuffer[i];
        }
        ADCConvertedValue = adc_sum/ADC_BUF_SIZE;
        Temperature = ADC_ConverValueToTemperature(ADCConvertedValue);
        log_info("ADC temperature sensor: %.2f C\r\n",Temperature);  

        Delay_ms(1000);
    }
}


/**
 * @brief  Configures the different system clocks.
 */
void RCC_Configuration(void)
{
    /* Enable peripheral clocks */
    RCC_EnableAHBPeriphClk(RCC_AHB_PERIPH_DMA, ENABLE);
    /* Enable GPIOB clocks */
    RCC_EnableAPB2PeriphClk(RCC_APB2_PERIPH_GPIOB, ENABLE);
    /* Enable ADC clocks */
    RCC_EnableAHBPeriphClk(RCC_AHB_PERIPH_ADC, ENABLE);
        
    RCC_ConfigAdcClk(RCC_ADCCLK_SRC_AUDIOPLL);

    /* enable ADC 4M clock */
    RCC_Enable_ADC_CLK_SRC_AUDIOPLL(ENABLE);
}


/**
 * @brief  Configures the different GPIO ports.
 */
void GPIO_Configuration(void)
{
    GPIO_InitType GPIO_InitStructure;

    GPIO_InitStruct(&GPIO_InitStructure);
    /* Configure PB.10 (ADC Channel1) PB.7 (ADC Channel4) as analog input --------*/
    GPIO_InitStructure.Pin       = GPIO_PIN_10|GPIO_PIN_7;
    GPIO_InitStructure.GPIO_Mode = GPIO_MODE_ANALOG;
    GPIO_InitPeripheral(GPIOB, &GPIO_InitStructure);
}


#ifdef USE_FULL_ASSERT

/**
 * @brief  Reports the name of the source file and the source line number
 *         where the assert_param error has occurred.
 * @param file pointer to the source file name
 * @param line assert_param error line source number
 */
void assert_failed(const uint8_t* expr, const uint8_t* file, uint32_t line)
{
    /* User can add his own implementation to report the file name and line number,
     ex: printf("Wrong parameters value: file %s on line %d\r\n", file, line) */

    while (1)
    {
    }
}

#endif

/**
 * @}
 */

/**
 * @}
 */

/*************** (C) COPYRIGHT Nations Technologies Inc *****END OF FILE***************/

此部分不修改

3.1.3 编译下载

N32WB03xSTB开发板自带下载器，官方已经配置好了，直接连接Type-C编译下载

3.1.4 调试验证

打开串口调试助手，修改相关配置。连接开发板，打印效果如下

此时可以用手指捂住芯片，温度会升高
，也会有相关大小变化

[11:43:40.101]收←◆
this is adc temperature sensor read demo.
ADC temperature sensor: 25.00 C

[11:43:41.134]收←◆ADC temperature sensor: 25.47 C

[11:43:42.161]收←◆ADC temperature sensor: 24.53 C

[11:43:43.189]收←◆ADC temperature sensor: 24.07 C

[11:43:44.218]收←◆ADC temperature sensor: 25.47 C

[11:43:45.244]收←◆ADC temperature sensor: 25.93 C

[11:43:46.271]收←◆ADC temperature sensor: 26.87 C

[11:43:47.299]收←◆ADC temperature sensor: 26.40 C

[11:43:48.326]收←◆ADC temperature sensor: 26.40 C

[11:43:49.352]收←◆ADC temperature sensor: 26.87 C

实验就结束啦！

4. 小结

0