RT-Thread-[N32G457] 基于RT-Thread和N32G457的简易便捷式可调电压源RT-Thread问答社区

[N32G457] 基于RT-Thread和N32G457的简易便捷式可调电压源

发布于 2022-03-02 20:57:35 浏览：1493 订阅该版

本设计是用来参加《创新“芯”引擎 | 国民技术N32G457 RT-Thread设计大赛》的作品。初衷是由于做军品要求国产化，所以最近也一直在测试国内不同厂家的32芯片的性能以及开发便捷性和最重要的稳定性等问题。之前也一直在用RTT做开发。浏览官网的时候发现有这个比赛，就顺便参加一下。至于做什么，肯定不能做我工作上的东西，都是军品保密的。只能想一些简单的。正好想到平常测试，特别是外出测试，经常因为电源问题而苦恼。于是想做一款简易的可调电压源，这样只需要带一个充电宝，就可以输出1~35V的电压，峰值电流基本能达到5A以上。也就可以驱动大多数的设备了。当然，功耗大的设备需要大充电宝才能工作时间长一些，但至少解决了供电电压不匹配的问题，可以应急使用了。
由于此比赛要求用官方给的核心板做开发，所以计划先简单实现一下主体功能。后面再具体做板实现整体功能。这次的测试硬件如下图，N32的最小系统板加一块我这边做其它测试的板子。这块板子只用了LTC3780部分的电路。
![国民技术核心板2.jpg](https://oss-club.rt-thread.org/uploads/20220302/ab7014df5d5dbba136e2c2430ea8054c.jpg.webp)
具体电路如下图：
![image.png](https://oss-club.rt-thread.org/uploads/20220302/243916a254c41c5ad5a4969be8423520.png.webp)
其中TEC-对地就是最终的电源输出接口，TEC_DAC为输出电压调整端口，接N32板的PA4引脚。TEC_i为输出电流检测端口，接N32板的PC1引脚。电源输出对地飞了个110K和10K的分压电阻，分压短点接N32板的PC0引脚，用于测量输出电压值（暂时没有对测量电压进行标定）。
测试版没有做显示界面（不太想飞线接屏了🤣）。取而代之的是shell界面。设置电压和电流值也用的shell命令。后面做电路的时候再改成显示屏和按键以及编码器旋钮的交互。测试界面如下：
![image.png](https://oss-club.rt-thread.org/uploads/20220302/7f562f93527b04e957873ddd66e870ae.png)
具体实现了shell命令修改电压值，电流值。输出电压和电流反馈的ADC采集。实时显示当前输出功率。PID控制输出电压值。电流超过电流设置值时触发限流保护，降低电压。按特定波形输出电压的功能，暂时只做了正弦信号的。这个功能后续有需求再继续扩展其它信号。
程序方面，自认为RTT自带的一些驱动，效率不是很高，只适合特定场合的简单使用，或者算是提供了一个demo。实现具体功能的话，建议自己重写底层驱动。比如这次用的shell底层串口驱动框架和ADC驱动框架。我日常使用，大多数都是用其它系统板通过shell命令配置当前板子的各运行参数，这样比起人手输入命令，传输数据量就要高很多。底层处理效率低的话就会出现丢数据，丢指令和串口配置参数的时候CPU占用率过高的问题，所以要适应这种场合我都是要重写底层驱动，加入收发FIFO。读写都只对软件的FIFO接口，不用等待硬件的真正的发送和接收完成，提高了代码执行效率。但这次的测试功能，都是人手输入shell命令，所以这部分驱动我没有再改动，就用的原有的，针对于这种测试需求倒是足够了。但参加比赛，总要在代码上有点贡献，所以这次主要改动的是ADC的底层驱动，加入了个人在工作中对ADC使用的一些不成熟的理解，希望能帮助到有需要的朋友。下面做详细说明：
如下是官方驱动，enable ADC通道和读ADC数据的代码：
    ```
static rt_err_t n32_adc_enabled(struct rt_adc_device *device, rt_uint32_t channel, rt_bool_t enabled)
{
    ADC_Module *n32_adc_handler;
    ADC_InitType ADC_InitStructure;
    RT_ASSERT(device != RT_NULL);
    n32_adc_handler = device->parent.user_data;

n32_msp_adc_init(n32_adc_handler);

ADC_InitStruct(&ADC_InitStructure);
    ADC_InitStructure.WorkMode              = ADC_WORKMODE_INDEPENDENT;
    ADC_InitStructure.MultiChEn             = DISABLE;
    ADC_InitStructure.ContinueConvEn        = DISABLE;
    ADC_InitStructure.ExtTrigSelect         = ADC_EXT_TRIGCONV_NONE;
    ADC_InitStructure.DatAlign              = ADC_DAT_ALIGN_R;
    ADC_InitStructure.ChsNumber             = 1;
    ADC_Init(n32_adc_handler, &ADC_InitStructure);

/* ADCx regular channels configuration */
    ADC_ConfigRegularChannel(n32_adc_handler, n32_adc_get_channel(channel), 1, ADC_SAMP_TIME_28CYCLES5);

if (((n32_adc_handler == ADC2) || (n32_adc_handler == ADC2))
        && ((n32_adc_get_channel(channel) == ADC_CH_16) || (n32_adc_get_channel(channel) == ADC_CH_18)))
    {
        ADC_EnableTempSensorVrefint(ENABLE);
    }

/* Enable ADCx */
    ADC_Enable(n32_adc_handler, ENABLE);

/* Start ADCx calibration */
    ADC_StartCalibration(n32_adc_handler);
    /* Check the end of ADCx calibration */
    while(ADC_GetCalibrationStatus(n32_adc_handler));

if (enabled)
    {
        /* Enable ADC1 */
        ADC_Enable(n32_adc_handler, ENABLE);
    }
    else
    {
        /* Enable ADCx */
        ADC_Enable(n32_adc_handler, DISABLE);
    }

return RT_EOK;
}
static rt_err_t n32_get_adc_value(struct rt_adc_device *device, rt_uint32_t channel, rt_uint32_t *value)
{
    ADC_Module *n32_adc_handler;

RT_ASSERT(device != RT_NULL);
    RT_ASSERT(value != RT_NULL);

n32_adc_handler = device->parent.user_data;

/* Start ADCx Software Conversion */
    ADC_EnableSoftwareStartConv(n32_adc_handler, ENABLE);

/* Wait for the ADC to convert */
    while(ADC_GetFlagStatus(n32_adc_handler, ADC_FLAG_ENDC) == RESET);

/* get ADC value */
    *value = ADC_GetDat(n32_adc_handler);

return RT_EOK;
}
```
首先enable里面初始化ADC就已经写死了关掉了多通道采集，关掉了连续转换。规则组中也只能加入一个通道。所以，同一时刻只能enable一个通道，转换完毕后再enable下一个通道。每次读取都要使能软件触发转换，然后等待转换完成，然后再读取转换结果返回。这现然不是高效的做法，while等待的时候CPU什么都做不了，也不能调度去执行其它线程的任务。只适用于很偶然的读取一下ADC数据。而大多数读取ADC数据基本都是要读取大量数据，做一些平滑滤波或中值滤波，最终得到一些稳定的数据。现然这个框架很难实现此功能，就算勉强用一个线程频繁的去读取ADC数据来实现此功能，那估计强大的32芯片也基本干不了别的了。144M的主频，说高不高，但说低也不低，又有FPU可以并行执行一些浮点运算指令，利用好了还是可以完成很多事情的。感觉官方ADC驱动框架也基本只限于简单的demo使用。于是加入了如下自己的ADC驱动程序：
   ```
#define ADC1_BUF1_UPDATE_EVENT      0x00000001
#define ADC1_BUF2_UPDATE_EVENT      0x00000002

#define ADC_VREFINT_VAL             1497.89

#ifdef  BSP_USING_USER_ADC1
    user_adc_config adc1_config =
    {
        .ADC_Handler = ADC1,
        .name        = "user_adc1",
        .RCC_APB2_PERIPH_GPIOX = RCC_APB2_PERIPH_GPIOC,
        .regular_channels = {
                {ADC_CH_18, RT_NULL, RT_NULL},      //rank1 Vrefint
                {ADC_CH_16, RT_NULL, RT_NULL},      //rank2 temp_cup
                {ADC_CH_6, GPIOC, GPIO_PIN_0},      //rank3 out_voltage
                {ADC_CH_7, GPIOC, GPIO_PIN_1}       //rank4 out_current
        }
    };
    uint16_t user_adc1_val_buf[2][USER_ADC1_AVE_N * USER_ADC1_REGULAR_CH];
    float adc1_ave_buf[USER_ADC1_REGULAR_CH-1];
    rt_thread_t adc_data_handle_thread;
    rt_event_t adc_update_event;
#endif

#ifdef  BSP_USING_USER_ADC2
    user_adc_config adc2_config =
    {
        .ADC_Handler = ADC2,
        .name        = "user_adc2",
    };
#endif

void AdcDataHandleEntry(void *parameter);

rt_err_t user_adc_init(rt_device_t dev)
{
    GPIO_InitType GPIO_InitCtlStruct;
    GPIO_InitStruct(&GPIO_InitCtlStruct);
    RT_ASSERT(dev != RT_NULL);
    ADC_Module *ADCx = (ADC_Module *)dev->user_data;
    ADC_InitType ADC_InitStructure;

adc_update_event = rt_event_create("adc_update", RT_IPC_FLAG_PRIO);

if(adc_update_event != RT_NULL)
    {
        adc_data_handle_thread = rt_thread_create("adc_data_handle", AdcDataHandleEntry, RT_NULL, 2048, 1, 10);
        if(adc_data_handle_thread != RT_NULL)
            rt_thread_startup(adc_data_handle_thread);
    }

#ifdef BSP_USING_USER_ADC1
    DMA_InitType ADC1_DMA_InitStructure;
    if(ADCx == ADC1)
    {
         /* ADC1 & GPIO clock enable */
         RCC_EnableAHBPeriphClk(RCC_AHB_PERIPH_ADC1 | RCC_AHB_PERIPH_DMA1, ENABLE);
         ADC_ConfigClk(ADC_CTRL3_CKMOD_AHB,RCC_ADCHCLK_DIV8);
         RCC_EnableAPB2PeriphClk(adc1_config.RCC_APB2_PERIPH_GPIOX, ENABLE);

ADC_InitStruct(&ADC_InitStructure);
         ADC_InitStructure.WorkMode              = ADC_WORKMODE_INDEPENDENT;
         ADC_InitStructure.MultiChEn             = ENABLE;
         ADC_InitStructure.ContinueConvEn        = ENABLE;
         ADC_InitStructure.ExtTrigSelect         = ADC_EXT_TRIGCONV_NONE;
         ADC_InitStructure.DatAlign              = ADC_DAT_ALIGN_R;
         ADC_InitStructure.ChsNumber             = USER_ADC1_REGULAR_CH;
         ADC_Init(ADCx, &ADC_InitStructure);

/* Configure ADC Channel as analog input */
         for(int i=0; i<USER_ADC1_REGULAR_CH; i++)
         {
             if(adc1_config.regular_channels[i].channel <= ADC_CH_11)
             {
                 GPIO_InitCtlStruct.Pin = adc1_config.regular_channels[i].GPIO_Pin;
                 GPIO_InitCtlStruct.GPIO_Speed = GPIO_Speed_2MHz;
                 GPIO_InitCtlStruct.GPIO_Mode = GPIO_Mode_AIN;
                 GPIO_InitPeripheral(adc1_config.regular_channels[i].GPIOX, &GPIO_InitCtlStruct);
             }
             /* ADCx regular channels configuration */
             ADC_ConfigRegularChannel(ADCx, adc1_config.regular_channels[i].channel, i+1, ADC_SAMP_TIME_239CYCLES5);

if ((adc1_config.regular_channels[i].channel == ADC_CH_16) || (adc1_config.regular_channels[i].channel == ADC_CH_18))
             {
                 ADC_EnableTempSensorVrefint(ENABLE);
             }
         }

/* Enable ADCx */
         ADC_Enable(ADCx, ENABLE);

/* Start ADCx calibration */
         ADC_StartCalibration(ADCx);
         /* Check the end of ADCx calibration */
         while(ADC_GetCalibrationStatus(ADCx));

ADC_Enable(ADCx, ENABLE);

ADC1_DMA_InitStructure.BufSize = USER_ADC1_AVE_N * USER_ADC1_REGULAR_CH * 2;
         ADC1_DMA_InitStructure.CircularMode = DMA_MODE_CIRCULAR;
         ADC1_DMA_InitStructure.DMA_MemoryInc = DMA_MEM_INC_ENABLE;
         ADC1_DMA_InitStructure.Direction = DMA_DIR_PERIPH_SRC;
         ADC1_DMA_InitStructure.Mem2Mem = DMA_M2M_DISABLE;
         ADC1_DMA_InitStructure.MemAddr = (uint32_t)user_adc1_val_buf;
         ADC1_DMA_InitStructure.MemDataSize = DMA_MemoryDataSize_HalfWord;
         ADC1_DMA_InitStructure.PeriphAddr = &(ADCx->DAT);
         ADC1_DMA_InitStructure.PeriphDataSize = DMA_PERIPH_DATA_SIZE_HALFWORD;
         ADC1_DMA_InitStructure.PeriphInc = DMA_PERIPH_INC_DISABLE;
         ADC1_DMA_InitStructure.Priority = DMA_PRIORITY_MEDIUM;
         DMA_Init(DMA1_CH1, &ADC1_DMA_InitStructure);

DMA_ConfigInt(DMA1_CH1, DMA_INT_HTX | DMA_INT_TXC, ENABLE);

ADC_EnableDMA(ADCx, ENABLE);

DMA_EnableChannel(DMA1_CH1, ENABLE);

NVIC_SetPriorityGrouping(4);
         NVIC_EnableIRQ(DMA1_Channel1_IRQn);

ADC_EnableSoftwareStartConv(ADCx, ENABLE);

}
    #endif

#ifdef BSP_USING_USER_ADC2
    if(ADCx == ADC2)
    {
         /* ADC2 & GPIO clock enable */
         RCC_EnableAHBPeriphClk(RCC_AHB_PERIPH_ADC2, ENABLE);
         ADC_ConfigClk(ADC_CTRL3_CKMOD_AHB,RCC_ADCHCLK_DIV8);
         RCC_EnableAPB2PeriphClk(RCC_APB2_PERIPH_GPIOC, ENABLE);

/* Configure ADC Channel as analog input */
         GPIO_InitCtlStruct.Pin = GPIO_PIN_1;
         GPIO_InitCtlStruct.GPIO_Speed = GPIO_Speed_2MHz;
         GPIO_InitCtlStruct.GPIO_Mode = GPIO_Mode_AIN;
         GPIO_InitPeripheral(GPIOC, &GPIO_InitCtlStruct);
    }
    #endif
    return RT_EOK;
}

rt_err_t user_adc_close(rt_device_t dev)
{
    ADC_Module *ADCx = (ADC_Module *)(dev->user_data);
    ADC_Enable(ADCx, DISABLE);
    if(ADCx == ADC1)
    {
        DMA_EnableChannel(DMA1_CH1, DISABLE);
        NVIC_DisableIRQ(DMA1_Channel1_IRQn);
        RCC_EnableAHBPeriphClk(RCC_AHB_PERIPH_ADC1 | RCC_AHB_PERIPH_DMA1, DISABLE);
    }
    rt_thread_delete(adc_data_handle_thread);
    rt_event_delete(adc_update_event);
    dev->flag &= ~(RT_DEVICE_FLAG_ACTIVATED);
    return RT_EOK;
}

static rt_size_t user_adc_read(rt_device_t dev, rt_off_t pos, void *buffer, rt_size_t size)
{
    rt_size_t i;
    user_adc_device_t adc = (user_adc_device_t)dev;
    float *value = (float *)buffer;

for (i = 0; i < size; i++)
    {
        if(pos+i < USER_ADC1_REGULAR_CH-1)
        {
            value[pos+i] = adc1_ave_buf[pos+i];
        }
        else {
            break;
        }
    }

return i;
}

static rt_err_t user_adc_control(rt_device_t dev, int cmd, void *args)
{
    rt_err_t result = RT_EOK;
    user_adc_device_t adc = (user_adc_device_t)dev;

return result;
}

rt_err_t user_hw_adc_register(user_adc_device_t device, const char *name, const void *user_data)
{
    rt_err_t result = RT_EOK;

device->parent.type = RT_Device_Class_Miscellaneous;
    device->parent.rx_indicate = RT_NULL;
    device->parent.tx_complete = RT_NULL;

device->parent.init        = user_adc_init;
    device->parent.open        = RT_NULL;
    device->parent.close       = user_adc_close;
    device->parent.read        = user_adc_read;
    device->parent.write       = RT_NULL;
    device->parent.control     = user_adc_control;

device->parent.user_data = (void *)user_data;

result = rt_device_register(&device->parent, name, RT_DEVICE_FLAG_RDONLY);

return result;
}

static int user_hw_adc_init(void)
{
    int result = RT_EOK;
    /* register ADC device */
#ifdef  BSP_USING_USER_ADC1
    if (user_hw_adc_register(&adc1_config.n32_adc_device, adc1_config.name, adc1_config.ADC_Handler) == RT_EOK)
    {
        LOG_D("%s register success", adc1_config.name);
    }
    else
    {
        LOG_E("%s register failed", adc1_config.name);
        result = -RT_ERROR;
    }
#endif

#ifdef  BSP_USING_USER_ADC2
    if (user_hw_adc_register(&adc2_config.n32_adc_device, adc2_config.name, adc2_config.ADC_Handler) == RT_EOK)
    {
        LOG_D("%s register success", adc2_config.name);
    }
    else
    {
        LOG_E("%s register failed", adc2_config.name);
        result = -RT_ERROR;
    }
#endif

return result;
}
INIT_COMPONENT_EXPORT(user_hw_adc_init);

void DMA1_Channel1_IRQHandler()
{
    if(DMA_GetIntStatus(DMA1_INT_HTX1,DMA1) == SET)
    {
        rt_event_send(adc_update_event, ADC1_BUF1_UPDATE_EVENT);
        DMA_ClrIntPendingBit(DMA1_INT_HTX1, DMA1);
    }
    if(DMA_GetIntStatus(DMA1_INT_TXC1,DMA1) == SET)
    {
        rt_event_send(adc_update_event, ADC1_BUF2_UPDATE_EVENT);
        DMA_ClrIntPendingBit(DMA1_INT_TXC1, DMA1);
    }
}

void GetAdcDataAverage(float *ave_buf, uint16_t *adc_buf)
{
    for(int i=0; i<USER_ADC1_REGULAR_CH-1; i++)
    {
        float adc_sum=0;
        for(int j=0; j<USER_ADC1_AVE_N; j++)
        {
            adc_sum += ADC_VREFINT_VAL * adc_buf[j*USER_ADC1_REGULAR_CH+i+1] / adc_buf[j*USER_ADC1_REGULAR_CH];
        }
        ave_buf[i] = adc_sum / USER_ADC1_AVE_N;
    }
}

void AdcDataHandleEntry(void *parameter)
{
    rt_uint32_t recved_event;
    while(1)
    {
        if(RT_EOK == rt_event_recv(adc_update_event, ADC1_BUF1_UPDATE_EVENT | ADC1_BUF2_UPDATE_EVENT, RT_EVENT_FLAG_OR | RT_EVENT_FLAG_CLEAR, -1, &recved_event))
        {
            if(recved_event & ADC1_BUF1_UPDATE_EVENT)
            {
                GetAdcDataAverage(adc1_ave_buf, user_adc1_val_buf[0]);
            }
            if(recved_event & ADC1_BUF2_UPDATE_EVENT)
            {
                GetAdcDataAverage(adc1_ave_buf, user_adc1_val_buf[1]);
            }
        }
    }
}
```
代码的大概思路是通过调用rt_device_open函数打开设备时，通过这里的Init函数初始化ADC，开启DMA。这里用的每通道的ADC数据采集量为100。利用DMA的一半传输完成中断实现双Buffer的功能，既传输一半完成后，处理前一半数据，完全传输完成后处理后一半数据。这样数据处理和DMA传输可以并行执行。在DMA中断中发送对应的event。开启一个高优先级线程，堵塞等待DMA传输完成事件，分别处理对应的数据。这里没有做中值滤波，只做了简单的平均滤波。测试了一下，采集ADC数据的频率大概是142帧/S。也就是大概7ms的时间出一组经过滤波的ADC数据。可以根据需求自行修改采样时间和平均点数。我这里计划后面做输出电压调节的PID线程用10ms的，所以这里控制在了10ms内。保证每次做PID运算都有新数据。
![ADC周期.png](https://oss-club.rt-thread.org/uploads/20220302/917d37e6179a89c16a785a9905cb30ba.png.webp)
我用的ADC的规则组加入了4个通道，第一通道是CH18，既Vrefint。第二通道是CH16，测了一下CPU温度，最终是要测量整体电路板的温度，根据电路板温度驱动散热风扇调控降温的。最终是用CPU温度调控还是在发热器件旁布一个热敏电阻后续再定。这里由于最小系统板和电源板分开的，CPU温度也测不到发热器件的温度。所以也只是简单的采集显示了一下。第三通道是PC0引脚，用于采集电压输出的反馈。第四通道是PC1引脚，用于采集电流反馈。测试板上面没有做采样电阻，而是用的一个霍尔感应器，量程是±10A的。所以精度有点差。最终也没必要用这个芯片，计划最终做板还是用采样电阻的方案，N32又自带运放，直接可以放大输入给ADC采集。
具体的ADC数据处理，是先根据电源纹波在短暂时间内差异不大的理论下，对每一次循环采集的4通道数据，根据内部基准电压做了个补偿。这样后面根据ADC数据计算的电压才是准确的。我这里实测的数据如下图：
![image.png](https://oss-club.rt-thread.org/uploads/20220302/a6a82d0adeea3bcb8ed9674884839b8a.png)
数组的0,4,8,12...就是保存的实时采集的Vrefint的ADC数据，而此时的VrefP的供电电压是3.265V。可以计算得到Vrefint的实际电压是1.2068。如下图是官方给的Vrefint的电压范围。
![image.png](https://oss-club.rt-thread.org/uploads/20220302/57bd77f95f90ec7a1a843f008188376d.png.webp)
根据实际的Vrefint可以推算出VrefP供电电压为标准的3.3V供电时，Vrefint的ADC转换值为1497.89。我看默认配置已经开启了FPU，所以这里直接用浮点数了，可以提高一点精度。
![FPU.png](https://oss-club.rt-thread.org/uploads/20220302/81fc4f54d36cb9b31e11490e2b47b38d.png.webp)
如下是main.c下实现的具体应用代码。比较简单，创建了一个电压控制线程，由于电压调控对于10ms的控制周期几乎没有滞后性，所以这里的PID控制，其实只用了PI。
```
#define LED1_PIN    90
#define LED2_PIN    91
#define LED3_PIN    67

#define CPU_Avg_Slope   -4.1
#define CPU_V25         1.33

uint16_t test_val=0;
uint8_t print_buf[128];

float read_adc_buf[USER_ADC1_REGULAR_CH-1];

rt_device_t OpenADCDevice(char *name);
rt_device_t adc1_dev=RT_NULL;
rt_device_t dac_dev=RT_NULL;

rt_tick_t shell_getchr_tick;
rt_thread_t voltage_ctrl_thread;
void VoltageCtrlEntry(void *parameter);

void plot_ui()
{
    rt_kprintf("\033[2J");
    rt_kprintf("\033[10;0H");
    rt_kprintf("    *******************************************\r\n");
    rt_kprintf("    *         voltage:");
    rt_kprintf("\033[1;40;31m%s\033[0m","   00.00");
    rt_kprintf("    V           *\r\n");
    rt_kprintf("    *         current:");
    rt_kprintf("\033[1;40;32m%s\033[0m","   0.000");
    rt_kprintf("    A           *\r\n");
    rt_kprintf("    *         power:  ");
    rt_kprintf("\033[1;40;34m%s\033[0m","   00.00");
    rt_kprintf("    W           *\r\n");
    rt_kprintf("    *         CPUTemp:   00.00    C           *\r\n");
    rt_kprintf("    *******************************************\r\n");
    rt_kprintf("\033[20;0H");
}

int main(void)
{
    rt_err_t result;
    uint32_t Speed = 500;
    /* set LED1 pin mode to output */
    rt_pin_mode(LED1_PIN, PIN_MODE_OUTPUT);
    rt_pin_mode(LED2_PIN, PIN_MODE_OUTPUT);
    rt_pin_mode(LED3_PIN, PIN_MODE_OUTPUT);

adc1_dev = OpenADCDevice("user_adc1");

voltage_ctrl_thread = rt_thread_create("VoltageCtrl", VoltageCtrlEntry, RT_NULL, 2048, 5, 10);
    if(voltage_ctrl_thread != RT_NULL)
        rt_thread_startup(voltage_ctrl_thread);

plot_ui();

while (1)
    {
        rt_pin_write(LED1_PIN, PIN_LOW);
        rt_pin_write(LED2_PIN, PIN_LOW);
        rt_pin_write(LED3_PIN, PIN_LOW);
        rt_thread_mdelay(Speed);
        rt_pin_write(LED1_PIN, PIN_HIGH);
        rt_pin_write(LED2_PIN, PIN_HIGH);
        rt_pin_write(LED3_PIN, PIN_HIGH);
        rt_thread_mdelay(Speed);

}
}

rt_device_t OpenADCDevice(char *name)
{
    rt_err_t result;
    rt_device_t adc_dev = rt_device_find(name);
    if(adc_dev != RT_NULL)
    {
        if(adc_dev->open_flag == RT_DEVICE_OFLAG_CLOSE)
        {
            result = rt_device_open(adc_dev, RT_DEVICE_OFLAG_RDONLY);
            if(result == RT_EOK)
            {
                rt_kprintf("%s opened!\r\n",name);
            }
            else {
                rt_kprintf("%s open err:%d!\r\n",name,result);
            }
        }
        else {
            rt_kprintf("%s is already opened!\r\n",name);
        }
    }
    else {
        rt_kprintf("not find %s device!\r\n",name);
    }
    return adc_dev;
}
void OpenADC1Device()
{
    adc1_dev = OpenADCDevice("user_adc1");
}
MSH_CMD_EXPORT(OpenADC1Device, open adc1 device and start adc1 conversion);

rt_err_t CloseADCDevice(char *name)
{
    rt_err_t result;
    rt_device_t adc_dev = rt_device_find(name);
    if(adc_dev != RT_NULL)
    {
        result = rt_device_close(adc_dev);
        if(result == RT_EOK)
        {
            rt_kprintf("%s closed!\r\n",name);
        }
        else {
            rt_kprintf("%s close err:%d!\r\n",name,result);
        }
    }
    else {
        rt_kprintf("not find %s device!\r\n",name);
    }
    return result;
}
void CloseADC1Device()
{
    CloseADCDevice("user_adc1");
}
MSH_CMD_EXPORT(CloseADC1Device, close adc1 device and stop adc1 conversion);

void ReadADC1Val()
{
    if(adc1_dev != RT_NULL && adc1_dev->open_flag != RT_DEVICE_OFLAG_CLOSE)
    {
        rt_device_read(adc1_dev, 0, read_adc_buf, USER_ADC1_REGULAR_CH-1);

sprintf(print_buf, "ADC:%f,%f,%f,%f\r\n", read_adc_buf[0], read_adc_buf[1], read_adc_buf[2], read_adc_buf[3]);
        rt_kprintf(print_buf);
    }
    else {
        rt_kprintf("user_adc1 dev not opened!\r\n");
    }
}
MSH_CMD_EXPORT(ReadADC1Val, read adc1 all channel val);

void get_shell_getchr_tick()
{
    shell_getchr_tick = rt_tick_get();
}

float SetVoltageVal = 5.0;      //V

float SetCurrentVal = 3.0;         //A

float VoltagePID_P = 100;
float VoltagePID_I = 50;

float user_atof(char *str)
{
    float val;
    char *ch_p=RT_NULL;
    do{
        if(*str == 0)
            return 0;
        if(*str == ' ')
        {
            str++;
        }
        else {
            break;
        }
    }
    while(1);
    ch_p = strchr(str , '.');
    int valH = atoi(str);
    float valL=0;
    if(ch_p > 0)
        valL = atoi(ch_p+1);
    do{
        if(valL >= 1)
        {
            valL /= 10;
        }
        else {
            break;
        }
    }while(1);
    val = valH + valL;
    return val;
}

float Sin_vpp=0, Sin_offset=0, Sin_cycle=0, Singal_Cycle_step=0;
void EnSinOut(int argc, char **argv)
{
    if(argc >= 2)
    {
        if(*argv[1] == '?')
        {
            sprintf(print_buf,"Vpp:%f, Offset:%f, Cycle:%f\r\n", Sin_vpp, Sin_offset, Sin_cycle);
            rt_kprintf(print_buf);
        }
        else if(argc >= 4)
        {
            float val = user_atof(argv[1]);
            if(val >=0 && val <=35)
            {
                Sin_vpp = val;
            }
            else {
                sprintf(print_buf,"Error:Out range[0,35]! Vpp:%fV\r\n", Sin_vpp);
                rt_kprintf(print_buf);
            }
            val = user_atof(argv[2]);
            if(val >=0 && val <=35)
            {
                Sin_offset = val;
            }
            else {
                sprintf(print_buf,"Error:Out range[0,35]! Offset:%fV\r\n", Sin_offset);
                rt_kprintf(print_buf);
            }
            val = user_atof(argv[3]);
            if(val >=1 && val <=100)
            {
                Sin_cycle = val;
                Singal_Cycle_step = 2*3.1415926/100/Sin_cycle;
            }
            else {
                sprintf(print_buf,"Error:Out range[1,100]! Cycle:%fS\r\n", Sin_cycle);
                rt_kprintf(print_buf);
            }
            sprintf(print_buf,"Vpp:%fV, Offset:%fV, Cycle:%fS\r\n", Sin_vpp, Sin_offset, Sin_cycle);
            rt_kprintf(print_buf);
        }
        else {
            rt_kprintf("EnSinOut [vpp offset cycle]\r\n");
        }
    }
    else {
        rt_kprintf("EnSinOut [vpp offset cycle]\r\n");
    }
}
MSH_CMD_EXPORT(EnSinOut, enable sinusoidal signal out);

void SetVoltage(int argc, char **argv)
{
    if(argc >= 2)
    {
        if(*argv[1] == '?')
        {
            sprintf(print_buf,"SetVoltageVal:%f\r\n", SetVoltageVal);
            rt_kprintf(print_buf);
        }
        else {
            float val = user_atof(argv[1]);
            if(val >=0 && val <=35)
            {
                Sin_vpp = 0;
                SetVoltageVal = val;
                sprintf(print_buf,"SetVoltageVal:%f\r\n", SetVoltageVal);
                rt_kprintf(print_buf);
            }
            else {
                sprintf(print_buf,"Error:Out range[0,35]! SetVoltageVal:%f\r\n", SetVoltageVal);
                rt_kprintf(print_buf);
            }
        }
    }
    else {
        rt_kprintf("SetVoltage [val]\r\n");
    }
}
MSH_CMD_EXPORT(SetVoltage, set voltage val);

void SetCurrent(int argc, char **argv)
{
    if(argc >= 2)
    {
        if(*argv[1] == '?')
        {
            sprintf(print_buf,"SetCurrentVal:%f\r\n", SetCurrentVal);
            rt_kprintf(print_buf);
        }
        else {
            float val = user_atof(argv[1]);
            if(val >=0 && val <=5)
            {
                SetCurrentVal = val;
                sprintf(print_buf,"SetCurrentVal:%f\r\n", SetCurrentVal);
                rt_kprintf(print_buf);
            }
            else {
                sprintf(print_buf,"Error:Out range[0,5]! SetCurrentVal:%f\r\n", SetCurrentVal);
                rt_kprintf(print_buf);
            }
        }
    }
    else {
        rt_kprintf("SetCurrent [val]\r\n");
    }
}
MSH_CMD_EXPORT(SetCurrent, set current val);

void VoltageCtrlEntry(void *parameter)
{
    uint8_t wait_i=0, replot_flag=0, overcurrent_flag=0;
    float cpu_temp_ave=0, voltage_ave=0, current_ave=0;
    dac_dev = rt_device_find("dac");
    uint32_t ch = 1;
    int32_t dac_val = 4095;
    rt_device_control(dac_dev, RT_DAC_CMD_ENABLE, &ch);
    rt_device_open(dac_dev, RT_DEVICE_OFLAG_RDWR);
    rt_device_write(dac_dev, ch, &dac_val, 1);

float Voltage_err=0, Voltage_err_old=0, Voltage_err_sum=0;

float CtrlVoltage=0;

float Singal_Cycle_i=0;

rt_thread_sleep(100);
    while(1)
    {
        if(adc1_dev != RT_NULL && adc1_dev->open_flag != RT_DEVICE_OFLAG_CLOSE)
        {
            rt_device_read(adc1_dev, 0, read_adc_buf, USER_ADC1_REGULAR_CH-1);
            float cpu_temp = (CPU_V25 - read_adc_buf[0] * 3.3 / 4096) * 1000 / CPU_Avg_Slope + 25;
            float voltage = read_adc_buf[1] * 3.3 / 4096 * 12;
            float current = -(read_adc_buf[2] * 3.3 / 4096 - 1.65)/0.132;
            if(current < 0)
                current = 0;

if(Sin_vpp > 0.0001)        //使能正弦信号输出
            {
                Singal_Cycle_i = fmod(Singal_Cycle_i + Singal_Cycle_step, 2*3.1415926);
                SetVoltageVal = Sin_offset + Sin_vpp / 2 * sin(Singal_Cycle_i);
            }

if(current <= SetCurrentVal)
            {
                if(overcurrent_flag)
                {
                    if(CtrlVoltage < SetVoltageVal-0.1)
                    {
                        CtrlVoltage += 0.1;
                    }
                    else if(CtrlVoltage > SetVoltageVal+0.1)
                    {
                        CtrlVoltage -= 0.1;
                    }
                    else {
                        CtrlVoltage = SetVoltageVal;
                        overcurrent_flag = 0;
                    }
                }
                else {
                    CtrlVoltage = SetVoltageVal;
                }
            }
            else {
                overcurrent_flag = 1;
                CtrlVoltage -= 0.1;
            }

Voltage_err = voltage - CtrlVoltage;
            if(Voltage_err < 0.1 && Voltage_err > -0.1)
            {
                Voltage_err_sum += Voltage_err;
            }

if(Voltage_err_old * Voltage_err < 0)
            {
                Voltage_err_sum = 0;
            }

if(Voltage_err_sum > 2)
            {
                Voltage_err_sum = 2;
            }
            else if(Voltage_err_sum < -2)
            {
                Voltage_err_sum = -2;
            }

Voltage_err_old = Voltage_err;

dac_val += VoltagePID_P * Voltage_err + VoltagePID_I * Voltage_err_sum;
            if(dac_val < 0)
            {
                dac_val = 0;
            }
            else if(dac_val > 4095)
            {
                dac_val = 4095;
            }
            rt_device_write(dac_dev, ch, &dac_val, 1);

cpu_temp_ave += cpu_temp;
            voltage_ave += voltage;
            current_ave += current;

if(wait_i++ >= 100)
            {
                if(rt_tick_get() - shell_getchr_tick > 5000)
                {
                    if(replot_flag)
                    {
                        plot_ui();
                        replot_flag = 0;
                    }
                    sprintf(print_buf,"%.2f ",voltage_ave / 101);
                    rt_kprintf("\033[11;26H");
                    rt_kprintf("\033[1;40;31m%s\033[0m",print_buf);

sprintf(print_buf,"%.3f ",current_ave / 101);
                    rt_kprintf("\033[12;26H");
                    rt_kprintf("\033[1;40;32m%s\033[0m",print_buf);

sprintf(print_buf,"%.3f ",voltage_ave / 101 * current_ave / 101);
                    rt_kprintf("\033[13;26H");
                    rt_kprintf("\033[1;40;34m%s\033[0m",print_buf);

sprintf(print_buf,"%.2f",cpu_temp_ave / 101);
                    rt_kprintf("\033[14;26H");
                    rt_kprintf(print_buf);
                    rt_kprintf("\033[20;0H");
                }
                else {
                    replot_flag = 1;
                }
                wait_i = 0;
                cpu_temp_ave = 0;
                voltage_ave = 0;
                current_ave = 0;
            }
        }
        rt_thread_sleep(RT_TICK_PER_SECOND/100);
    }
}
```
具体代码，有兴趣的朋友可以看一下，我就不一点点介绍分析了。测试用的，代码写的也比较随意，也没做注释。希望能对有需要的朋友提供帮助。也可以在此基础上再继续优化完善代码。后面等上传了演示视频再附上视频地址。祝大家工作学习开心愉快。
[功能演示视频](https://www.bilibili.com/video/BV1Wa411h7Di?p=1&share_medium=android&share_plat=android&share_session_id=0292055d-3fee-4063-a2c2-f72f36c7ac64&share_source=WEIXIN&share_tag=s_i×tamp=1646356356&unique_k=KAH3D2I)
[源码地址](https://gitee.com/chengjili/n32g457_rtthread.git)