STM32配置读取双路24位模数转换（24bit ADC）芯片CS1238数据STM32配置读取双路24位模数转换（24bit ADC）芯片CS1238数据

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我是靠谱客的博主单纯悟空，这篇文章主要介绍STM32配置读取双路24位模数转换（24bit ADC）芯片CS1238数据STM32配置读取双路24位模数转换（24bit ADC）芯片CS1238数据，现在分享给大家，希望可以做个参考。

STM32配置读取双路24位模数转换（24bit ADC）芯片CS1238数据

CS1238是一款国产双路24位ADC芯片，与CS1238对应的单路24位ADC芯片是CS1237，功能上相当于HX711和TM7711的组合。其功能如下所示：
在这里插入图片描述
市面上的模块：

STM32电路连接

CS1238内部原理如下所示, VDD是DVDD和AVDD的合并：
在这里插入图片描述
有单独的参考电压输入设置管脚，以及内部输出与VDD同电压的参考输出电压，可选连接到参考输入电压管脚：

所以如果REFIN要设置为5V, 则VDD也要设置为5V，因为CS1238的DOUT管脚是输入输出双向管脚，所以要增加电路才能实现和3.3V STM32芯片的连接访问。这里先介绍VDD和REFIN都是3.3V的场景，所以可以和STM32芯片直接连接。

CS1238测试电路

CS1238典型的应用连接到惠斯通电桥，接收差分电压。简单测试可以采用如下方式：
在这里插入图片描述
当可调电阻器为10欧姆时，IN+和IN-差分电压为(3.3/(4700+4700+10))*10 = 3.507mV。可以微调可调电位器的阻值，调整输出差模电压。

如果CS1238差分输入是单端信号，在差分输入两端连接一个大电阻如1M欧姆。如果CS1238差分输入是差分信号，则根据阻抗要求跨接一个匹配电阻如100欧姆。

CS1238访问协议

CS1238通过控制时钟管脚输出低电平指示正常工作状态，然后识别数据输入管脚DOUT/nRDY的低电平状态判断当前已完成转换并可读取数据，然后发送出24个时钟波形，并在每个时钟波形的下降沿读取数据位，先读到的是24位采样数据的高位。在24个时钟后，还可以发送3个时钟波形，即第25~27的时钟，在第25个时钟读到的电平反应配置寄存器更新状态。第26个时钟读到的电平始终为0无意义表达。

DOUT/nRDY是三目的管脚，除了作为转换完成的状态指示，作为输出，也作为输入。而且MCU对CS1238输出时，因为CS1238输入内阻比较小，不能通过外部上拉提供电压输入，所以MCU要采用推挽方式(Push-pull)输出高电平给CS1238。而MCU接收数据时，要配置在输入模式或者输出开漏(Open-drain)逻辑高输出模式，都可以读取到管脚状态，因为从输出OD到输出PP内部电路切换更平滑，所以这里STM32采用输出OD作为读模式，输出PP作为写模式的配置。

CS1238在控制寄存器的写入和读取方面的时序描述如下：
在这里插入图片描述

STM32工程配置

这里采用STM32F103C6T6和STM32CUBEIDE开发环境，实现CS1238的ADC数据读取代码。

首先配置基本工程和时钟系统：
在这里插入图片描述

STM32F103支持USB，可以实现虚拟串口，所以进行USB的配置，采用默认设置接口，另外配置UART2作为可选通讯口。

然后配置UART2：

选择具有FT特征的PB0和PB1作为与CS1238通讯的管脚，PB0作为时钟管脚配置为Push-pull，PB1作先配置为Open-drain，然后再程序代码里进行切换Push-pull。
在这里插入图片描述
保存并生成初始代码：

STM32工程代码

代码主要实现微秒级的时序控制，采用的微秒延时函数参考： STM32 HAL us delay（微秒延时）的指令延时实现方式及优化
STM32虚拟串口的设置可以参考： STM32 USB VCOM和HID的区别，配置及Echo功能实现（HAL）
编译时需要采用节省存储的编译方式，参考： STM32 region `FLASH‘ overflowed by xxx bytes 问题解决

代码在USB的控制文件里，将USB接收到的字节赋值给全局变量cmd，用来控制逻辑执行：

在收到0x01时，按照发送24个时钟的模式读取CS1238 24bit数据
在收到0x02时，按照发送27个时钟的模式读取CS1238 24bit数据和配置寄存器更新状态信息
在收到0x03时，读取CS1238配置寄存器字节数据
在收到字节最高位为1的cmd时，识别为要写入CS1238配置寄存器操作，将cmd的最高位1改为0，然后发送到CS1238配置寄存器

在这里插入图片描述
main.c文件完整代码如下：

复制代码

/* USER CODE BEGIN Header */
/**
  ******************************************************************************
  * @file           : main.c
  * @brief          : Main program body
  ******************************************************************************
  * @attention
  *
  * Copyright (c) 2022 STMicroelectronics.
  * All rights reserved.
  *
  * This software is licensed under terms that can be found in the LICENSE file
  * in the root directory of this software component.
  * If no LICENSE file comes with this software, it is provided AS-IS.
  *
  ******************************************************************************
  */
//Written by Pegasus Yu in 2022
/* USER CODE END Header */
/* Includes ------------------------------------------------------------------*/
#include "main.h"
#include "usb_device.h"

/* Private includes ----------------------------------------------------------*/
/* USER CODE BEGIN Includes */
#include "string.h"
/* USER CODE END Includes */

/* Private typedef -----------------------------------------------------------*/
/* USER CODE BEGIN PTD */
__IO float usDelayBase;
void PY_usDelayTest(void)
{
  __IO uint32_t firstms, secondms;
  __IO uint32_t counter = 0;

firstms = HAL_GetTick()+1;
  secondms = firstms+1;

while(uwTick!=firstms) ;

while(uwTick!=secondms) counter++;

usDelayBase = ((float)counter)/1000;
}

void PY_Delay_us_t(uint32_t Delay)
{
  __IO uint32_t delayReg;
  __IO uint32_t usNum = (uint32_t)(Delay*usDelayBase);

delayReg = 0;
  while(delayReg!=usNum) delayReg++;
}

void PY_usDelayOptimize(void)
{
  __IO uint32_t firstms, secondms;
  __IO float coe = 1.0;

firstms = HAL_GetTick();
  PY_Delay_us_t(1000000) ;
  secondms = HAL_GetTick();

coe = ((float)1000)/(secondms-firstms);
  usDelayBase = coe*usDelayBase;
}

void PY_Delay_us(uint32_t Delay)
{
  __IO uint32_t delayReg;

__IO uint32_t msNum = Delay/1000;
  __IO uint32_t usNum = (uint32_t)((Delay%1000)*usDelayBase);

if(msNum>0) HAL_Delay(msNum);

delayReg = 0;
  while(delayReg!=usNum) delayReg++;
}
/* USER CODE END PTD */

/* Private define ------------------------------------------------------------*/
/* USER CODE BEGIN PD */
void Dout_OD_Mode(void);
void Dout_PP_Mode(void);
/* USER CODE END PD */

/* Private macro -------------------------------------------------------------*/
/* USER CODE BEGIN PM */
#define cs1238_rdy (HAL_GPIO_ReadPin(GPIOB,  GPIO_PIN_1)==0)?1:0

#define cs1238_clk_h HAL_GPIO_WritePin(GPIOB, GPIO_PIN_0, GPIO_PIN_SET)
#define cs1238_clk_l HAL_GPIO_WritePin(GPIOB, GPIO_PIN_0, GPIO_PIN_RESET)
#define cs1238_dout HAL_GPIO_ReadPin(GPIOB,  GPIO_PIN_1)

#define write_to_cs1238_dout_h HAL_GPIO_WritePin(GPIOB, GPIO_PIN_1, GPIO_PIN_SET)
#define write_to_cs1238_dout_l HAL_GPIO_WritePin(GPIOB, GPIO_PIN_1, GPIO_PIN_RESET)

#define WReg_CMD 0x65
#define RReg_CMD 0x56
/* USER CODE END PM */

/* Private variables ---------------------------------------------------------*/
UART_HandleTypeDef huart2;

/* USER CODE BEGIN PV */

/* USER CODE END PV */

/* Private function prototypes -----------------------------------------------*/
void SystemClock_Config(void);
static void MX_GPIO_Init(void);
static void MX_USART2_UART_Init(void);
/* USER CODE BEGIN PFP */

/* USER CODE END PFP */

/* Private user code ---------------------------------------------------------*/
/* USER CODE BEGIN 0 */
uint8_t cmd=0;
uint32_t cs1238_data;
uint32_t cs1238_data_max = 0;
/* USER CODE END 0 */

/**
  * @brief  The application entry point.
  * @retval int
  */
int main(void)
{
  /* USER CODE BEGIN 1 */
   uint8_t config_reg_update_status = 0;
   uint8_t config_reg = 0x0c; //config reg default value after power-up is 0x0c for CS1238

/* USER CODE END 1 */

/* MCU Configuration--------------------------------------------------------*/

/* Reset of all peripherals, Initializes the Flash interface and the Systick. */
  HAL_Init();

/* USER CODE BEGIN Init */

/* USER CODE END Init */

/* Configure the system clock */
  SystemClock_Config();

/* USER CODE BEGIN SysInit */

/* USER CODE END SysInit */

/* Initialize all configured peripherals */
  MX_GPIO_Init();
  MX_USART2_UART_Init();
  MX_USB_DEVICE_Init();
  /* USER CODE BEGIN 2 */
  PY_usDelayTest();
  PY_usDelayOptimize();

cs1238_clk_h;
  PY_Delay_us_t(120); //soft reset cs1238
  cs1238_clk_l;
  PY_Delay_us_t(10);

__HAL_UART_CLEAR_FLAG(&huart2, UART_FLAG_RXNE);
  HAL_UART_Receive_IT(&huart2, (uint8_t *)&cmd, 1);
  /* USER CODE END 2 */

/* Infinite loop */
  /* USER CODE BEGIN WHILE */
  while (1)
  {

if(cmd==0x01) //read value w/o update info
		  {
			  while(cs1238_rdy) ;
		      while(!cs1238_rdy) ;
		      cs1238_data = 0;
			  PY_Delay_us_t(1);

for(uint8_t i=1;i<=24;i++)
			  {
				  cs1238_clk_h;
				  PY_Delay_us_t(1);
				  cs1238_clk_l;
				  cs1238_data |=  (((uint32_t)cs1238_dout)<<(24-i));
				  PY_Delay_us_t(1);
			  }

while( CDC_Transmit_FS(&cs1238_data, 3) != USBD_OK ) PY_Delay_us_t(1);

}
      else if(cmd==0x02) //read value w/ update info
	  {
		  /*
		   * Dout value from CLK 25 indicates Config register was written new value already
		   * Dout value from CLK 26 gets 0 always without meaning
		   */

while(cs1238_rdy) ;
		      while(!cs1238_rdy);
			  cs1238_data = 0;
			  PY_Delay_us_t(1);

/*clk 1~24*/
			  for(uint8_t i=1;i<=24;i++)
			  {
				  cs1238_clk_h;
				  PY_Delay_us_t(1);
				  cs1238_clk_l;
				  cs1238_data |=  (((uint32_t)cs1238_dout)<<(24-i));
				  PY_Delay_us_t(1);
			  }

/*clk 25*/
			  cs1238_clk_h;
			  PY_Delay_us_t(1);
			  cs1238_clk_l;
			  config_reg_update_status = cs1238_dout;
			  PY_Delay_us_t(1);

/*clk 26*/
			  cs1238_clk_h;
			  PY_Delay_us_t(1);
			  cs1238_clk_l;
			  PY_Delay_us_t(1);

/*clk 27*/
			  cs1238_clk_h;
			  Dout_PP_Mode();
			  PY_Delay_us_t(1);
			  cs1238_clk_l;
			  PY_Delay_us_t(1);
			  Dout_OD_Mode();

while( CDC_Transmit_FS(&cs1238_data, 3) != USBD_OK ) PY_Delay_us_t(1);
		  while( CDC_Transmit_FS(&config_reg_update_status, 1) != USBD_OK ) PY_Delay_us_t(1);

}
	  else if(cmd==0x03) //Read config register
	  {
	      cmd = 0x00;

while(cs1238_rdy) ;
		      while(!cs1238_rdy);
			  cs1238_data = 0;
			  PY_Delay_us_t(1);

/*clk 1~24*/
			  for(uint8_t i=1;i<=24;i++)
			  {
				  cs1238_clk_h;
				  PY_Delay_us_t(1);
				  cs1238_clk_l;
				  PY_Delay_us_t(1);
			  }

/*clk 25*/
			  cs1238_clk_h;
			  PY_Delay_us_t(1);
			  cs1238_clk_l;
			  PY_Delay_us_t(1);

/*clk 26*/
			  cs1238_clk_h;
			  PY_Delay_us_t(1);
			  cs1238_clk_l;
			  PY_Delay_us_t(1);

/*clk 27*/
			  cs1238_clk_h;
			  Dout_PP_Mode();
			  PY_Delay_us_t(1);
			  cs1238_clk_l;
			  PY_Delay_us_t(1);

/*clk 28*/
			  cs1238_clk_h;
			  PY_Delay_us_t(1);
			  cs1238_clk_l;
			  PY_Delay_us_t(1);

/*clk 29*/
			  cs1238_clk_h;
			  PY_Delay_us_t(1);
			  cs1238_clk_l;
			  PY_Delay_us_t(1);

/*clk 30~36*/
			  for(uint8_t i=1;i<8;i++)
			  {
					  cs1238_clk_h;
					  if(((RReg_CMD<<i)&0x80)) write_to_cs1238_dout_h;
					  else write_to_cs1238_dout_l;
					  PY_Delay_us_t(1);
					  cs1238_clk_l;
					  PY_Delay_us_t(1);
			  }

/*clk 37*/
			  Dout_OD_Mode();
			  cs1238_clk_h;
			  PY_Delay_us_t(1);
			  cs1238_clk_l;
			  PY_Delay_us_t(1);

/*clk 38~45*/
			  config_reg = 0;
			  for(uint8_t i=0;i<8;i++)
			  {
					  cs1238_clk_h;
					  PY_Delay_us_t(1);
					  cs1238_clk_l;
					  config_reg |=  (cs1238_dout<<(7-i));
					  PY_Delay_us_t(1);
			  }

/*clk 46*/
			  Dout_PP_Mode();
			  cs1238_clk_h;
			  PY_Delay_us_t(1);
			  cs1238_clk_l;
			  PY_Delay_us_t(1);
			  Dout_OD_Mode();

while( CDC_Transmit_FS(&config_reg, 1) != USBD_OK ) PY_Delay_us_t(1);

}
	  else if(cmd&0x80) //Set config register
	  {
		  config_reg = cmd&0x7F; //Config register value to be sent
	      while(cs1238_rdy) ;
	      while(!cs1238_rdy);
		  cs1238_data = 0;
		  PY_Delay_us_t(1);

/*clk 1~24*/
		  for(uint8_t i=1;i<=24;i++)
		  {
			  cs1238_clk_h;
			  PY_Delay_us_t(1);
			  cs1238_clk_l;
			  PY_Delay_us_t(1);
		  }

/*clk 25*/
		  cs1238_clk_h;
		  PY_Delay_us_t(1);
		  cs1238_clk_l;
		  PY_Delay_us_t(1);

/*clk 26*/
		  cs1238_clk_h;
		  PY_Delay_us_t(1);
		  cs1238_clk_l;
		  PY_Delay_us_t(1);

/*clk 27*/
		  cs1238_clk_h;
		  Dout_PP_Mode();
		  PY_Delay_us_t(1);
		  cs1238_clk_l;
		  PY_Delay_us_t(1);

/*clk 28*/
		  cs1238_clk_h;
		  PY_Delay_us_t(1);
		  cs1238_clk_l;
		  PY_Delay_us_t(1);

/*clk 29*/
		  cs1238_clk_h;
		  PY_Delay_us_t(1);
		  cs1238_clk_l;
		  PY_Delay_us_t(1);

/*clk 30~36*/
		  for(uint8_t i=1;i<8;i++)
		  {
				  cs1238_clk_h;
				  if(((WReg_CMD<<i)&0x80)) write_to_cs1238_dout_h;
				  else write_to_cs1238_dout_l;
				  PY_Delay_us_t(1);
				  cs1238_clk_l;
				  PY_Delay_us_t(1);
		  }

/*clk 37*/
		  Dout_PP_Mode();
		  cs1238_clk_h;
		  PY_Delay_us_t(1);
		  cs1238_clk_l;
		  PY_Delay_us_t(1);

/*clk 38~45*/
		  for(uint8_t i=0;i<8;i++)
		  {
				  cs1238_clk_h;
				  if(((config_reg<<i)&0x80)) write_to_cs1238_dout_h;
				  else write_to_cs1238_dout_l;
				  PY_Delay_us_t(1);
				  cs1238_clk_l;
				  PY_Delay_us_t(1);
		  }

/*clk 46*/
		  Dout_PP_Mode();
		  cs1238_clk_h;
		  PY_Delay_us_t(1);
		  cs1238_clk_l;
		  PY_Delay_us_t(1);
		  Dout_OD_Mode();

while( CDC_Transmit_FS(&config_reg, 1) != USBD_OK ) PY_Delay_us_t(1);
	  cmd = 0;

}
	  else;

PY_Delay_us_t(500000);

/* USER CODE END WHILE */

/* USER CODE BEGIN 3 */
  }
  /* USER CODE END 3 */
}

/**
  * @brief System Clock Configuration
  * @retval None
  */
void SystemClock_Config(void)
{
  RCC_OscInitTypeDef RCC_OscInitStruct = {0};
  RCC_ClkInitTypeDef RCC_ClkInitStruct = {0};
  RCC_PeriphCLKInitTypeDef PeriphClkInit = {0};

/** Initializes the RCC Oscillators according to the specified parameters
  * in the RCC_OscInitTypeDef structure.
  */
  RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_HSE;
  RCC_OscInitStruct.HSEState = RCC_HSE_ON;
  RCC_OscInitStruct.HSEPredivValue = RCC_HSE_PREDIV_DIV1;
  RCC_OscInitStruct.HSIState = RCC_HSI_ON;
  RCC_OscInitStruct.PLL.PLLState = RCC_PLL_ON;
  RCC_OscInitStruct.PLL.PLLSource = RCC_PLLSOURCE_HSE;
  RCC_OscInitStruct.PLL.PLLMUL = RCC_PLL_MUL9;
  if (HAL_RCC_OscConfig(&RCC_OscInitStruct) != HAL_OK)
  {
    Error_Handler();
  }

/** Initializes the CPU, AHB and APB buses clocks
  */
  RCC_ClkInitStruct.ClockType = RCC_CLOCKTYPE_HCLK|RCC_CLOCKTYPE_SYSCLK
                              |RCC_CLOCKTYPE_PCLK1|RCC_CLOCKTYPE_PCLK2;
  RCC_ClkInitStruct.SYSCLKSource = RCC_SYSCLKSOURCE_PLLCLK;
  RCC_ClkInitStruct.AHBCLKDivider = RCC_SYSCLK_DIV1;
  RCC_ClkInitStruct.APB1CLKDivider = RCC_HCLK_DIV2;
  RCC_ClkInitStruct.APB2CLKDivider = RCC_HCLK_DIV1;

if (HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_2) != HAL_OK)
  {
    Error_Handler();
  }
  PeriphClkInit.PeriphClockSelection = RCC_PERIPHCLK_USB;
  PeriphClkInit.UsbClockSelection = RCC_USBCLKSOURCE_PLL_DIV1_5;
  if (HAL_RCCEx_PeriphCLKConfig(&PeriphClkInit) != HAL_OK)
  {
    Error_Handler();
  }
}

/**
  * @brief USART2 Initialization Function
  * @param None
  * @retval None
  */
static void MX_USART2_UART_Init(void)
{

/* USER CODE BEGIN USART2_Init 0 */

/* USER CODE END USART2_Init 0 */

/* USER CODE BEGIN USART2_Init 1 */

/* USER CODE END USART2_Init 1 */
  huart2.Instance = USART2;
  huart2.Init.BaudRate = 115200;
  huart2.Init.WordLength = UART_WORDLENGTH_8B;
  huart2.Init.StopBits = UART_STOPBITS_1;
  huart2.Init.Parity = UART_PARITY_NONE;
  huart2.Init.Mode = UART_MODE_TX_RX;
  huart2.Init.HwFlowCtl = UART_HWCONTROL_NONE;
  huart2.Init.OverSampling = UART_OVERSAMPLING_16;
  if (HAL_UART_Init(&huart2) != HAL_OK)
  {
    Error_Handler();
  }
  /* USER CODE BEGIN USART2_Init 2 */

/* USER CODE END USART2_Init 2 */

}

/**
  * @brief GPIO Initialization Function
  * @param None
  * @retval None
  */
static void MX_GPIO_Init(void)
{
  GPIO_InitTypeDef GPIO_InitStruct = {0};

/* GPIO Ports Clock Enable */
  __HAL_RCC_GPIOD_CLK_ENABLE();
  __HAL_RCC_GPIOA_CLK_ENABLE();
  __HAL_RCC_GPIOB_CLK_ENABLE();

/*Configure GPIO pin Output Level */
  HAL_GPIO_WritePin(GPIOB, GPIO_PIN_0, GPIO_PIN_RESET);

/*Configure GPIO pin Output Level */
  HAL_GPIO_WritePin(GPIOB, GPIO_PIN_1, GPIO_PIN_SET);

/*Configure GPIO pin : PB0 */
  GPIO_InitStruct.Pin = GPIO_PIN_0;
  GPIO_InitStruct.Mode = GPIO_MODE_OUTPUT_PP;
  GPIO_InitStruct.Pull = GPIO_NOPULL;
  GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_HIGH;
  HAL_GPIO_Init(GPIOB, &GPIO_InitStruct);

/*Configure GPIO pin : PB1 */
  GPIO_InitStruct.Pin = GPIO_PIN_1;
  GPIO_InitStruct.Mode = GPIO_MODE_OUTPUT_OD;
  GPIO_InitStruct.Pull = GPIO_PULLUP;
  GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_HIGH;
  HAL_GPIO_Init(GPIOB, &GPIO_InitStruct);

}

/* USER CODE BEGIN 4 */
void Dout_OD_Mode(void)
{
  GPIO_InitTypeDef GPIO_InitStruct = {0};

/* GPIO Ports Clock Enable */
  __HAL_RCC_GPIOB_CLK_ENABLE();

/*Configure GPIO pin Output Level */
  HAL_GPIO_WritePin(GPIOB, GPIO_PIN_1, GPIO_PIN_SET);

}

void Dout_PP_Mode(void)
{
  GPIO_InitTypeDef GPIO_InitStruct = {0};

/* GPIO Ports Clock Enable */
  __HAL_RCC_GPIOB_CLK_ENABLE();

/*Configure GPIO pin Output Level */
  HAL_GPIO_WritePin(GPIOB, GPIO_PIN_1, GPIO_PIN_SET);

/*Configure GPIO pin : PB1 */
  GPIO_InitStruct.Pin = GPIO_PIN_1;
  GPIO_InitStruct.Mode = GPIO_MODE_OUTPUT_PP;
  GPIO_InitStruct.Pull = GPIO_NOPULL;
  GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_HIGH;
  HAL_GPIO_Init(GPIOB, &GPIO_InitStruct);

}

void HAL_UART_RxCpltCallback(UART_HandleTypeDef *UartHandle)
{
	HAL_UART_Receive_IT(&huart2, (uint8_t *)&cmd, 1);
}
/* USER CODE END 4 */

/**
  * @brief  This function is executed in case of error occurrence.
  * @retval None
  */
void Error_Handler(void)
{
  /* USER CODE BEGIN Error_Handler_Debug */
  /* User can add his own implementation to report the HAL error return state */
  __disable_irq();
  while (1)
  {
  }
  /* USER CODE END Error_Handler_Debug */
}

#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
  * @retval None
  */
void assert_failed(uint8_t *file, uint32_t line)
{
  /* USER CODE BEGIN 6 */
  /* User can add his own implementation to report the file name and line number,
     ex: printf("Wrong parameters value: file %s on line %drn", file, line) */
  /* USER CODE END 6 */
}
#endif /* USE_FULL_ASSERT */

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/* USER CODE BEGIN Header */
/**
  ******************************************************************************
  * @file           : main.c
  * @brief          : Main program body
  ******************************************************************************
  * @attention
  *
  * Copyright (c) 2022 STMicroelectronics.
  * All rights reserved.
  *
  * This software is licensed under terms that can be found in the LICENSE file
  * in the root directory of this software component.
  * If no LICENSE file comes with this software, it is provided AS-IS.
  *
  ******************************************************************************
  */
//Written by Pegasus Yu in 2022
/* USER CODE END Header */
/* Includes ------------------------------------------------------------------*/
#include "main.h"
#include "usb_device.h"

/* Private includes ----------------------------------------------------------*/
/* USER CODE BEGIN Includes */
#include "string.h"
/* USER CODE END Includes */

/* Private typedef -----------------------------------------------------------*/
/* USER CODE BEGIN PTD */
__IO float usDelayBase;
void PY_usDelayTest(void)
{
  __IO uint32_t firstms, secondms;
  __IO uint32_t counter = 0;

  firstms = HAL_GetTick()+1;
  secondms = firstms+1;

  while(uwTick!=firstms) ;

  while(uwTick!=secondms) counter++;

  usDelayBase = ((float)counter)/1000;
}

void PY_Delay_us_t(uint32_t Delay)
{
  __IO uint32_t delayReg;
  __IO uint32_t usNum = (uint32_t)(Delay*usDelayBase);

  delayReg = 0;
  while(delayReg!=usNum) delayReg++;
}

void PY_usDelayOptimize(void)
{
  __IO uint32_t firstms, secondms;
  __IO float coe = 1.0;

  firstms = HAL_GetTick();
  PY_Delay_us_t(1000000) ;
  secondms = HAL_GetTick();

  coe = ((float)1000)/(secondms-firstms);
  usDelayBase = coe*usDelayBase;
}


void PY_Delay_us(uint32_t Delay)
{
  __IO uint32_t delayReg;

  __IO uint32_t msNum = Delay/1000;
  __IO uint32_t usNum = (uint32_t)((Delay%1000)*usDelayBase);

  if(msNum>0) HAL_Delay(msNum);

  delayReg = 0;
  while(delayReg!=usNum) delayReg++;
}
/* USER CODE END PTD */

/* Private define ------------------------------------------------------------*/
/* USER CODE BEGIN PD */
void Dout_OD_Mode(void);
void Dout_PP_Mode(void);
/* USER CODE END PD */

/* Private macro -------------------------------------------------------------*/
/* USER CODE BEGIN PM */
#define cs1238_rdy (HAL_GPIO_ReadPin(GPIOB,  GPIO_PIN_1)==0)?1:0

#define cs1238_clk_h HAL_GPIO_WritePin(GPIOB, GPIO_PIN_0, GPIO_PIN_SET)
#define cs1238_clk_l HAL_GPIO_WritePin(GPIOB, GPIO_PIN_0, GPIO_PIN_RESET)
#define cs1238_dout HAL_GPIO_ReadPin(GPIOB,  GPIO_PIN_1)

#define write_to_cs1238_dout_h HAL_GPIO_WritePin(GPIOB, GPIO_PIN_1, GPIO_PIN_SET)
#define write_to_cs1238_dout_l HAL_GPIO_WritePin(GPIOB, GPIO_PIN_1, GPIO_PIN_RESET)

#define WReg_CMD 0x65
#define RReg_CMD 0x56
/* USER CODE END PM */

/* Private variables ---------------------------------------------------------*/
UART_HandleTypeDef huart2;

/* USER CODE BEGIN PV */

/* USER CODE END PV */

/* Private function prototypes -----------------------------------------------*/
void SystemClock_Config(void);
static void MX_GPIO_Init(void);
static void MX_USART2_UART_Init(void);
/* USER CODE BEGIN PFP */

/* USER CODE END PFP */

/* Private user code ---------------------------------------------------------*/
/* USER CODE BEGIN 0 */
uint8_t cmd=0;
uint32_t cs1238_data;
uint32_t cs1238_data_max = 0;
/* USER CODE END 0 */

/**
  * @brief  The application entry point.
  * @retval int
  */
int main(void)
{
  /* USER CODE BEGIN 1 */
   uint8_t config_reg_update_status = 0;
   uint8_t config_reg = 0x0c; //config reg default value after power-up is 0x0c for CS1238

  /* USER CODE END 1 */

  /* MCU Configuration--------------------------------------------------------*/

  /* Reset of all peripherals, Initializes the Flash interface and the Systick. */
  HAL_Init();

  /* USER CODE BEGIN Init */

  /* USER CODE END Init */

  /* Configure the system clock */
  SystemClock_Config();

  /* USER CODE BEGIN SysInit */

  /* USER CODE END SysInit */

  /* Initialize all configured peripherals */
  MX_GPIO_Init();
  MX_USART2_UART_Init();
  MX_USB_DEVICE_Init();
  /* USER CODE BEGIN 2 */
  PY_usDelayTest();
  PY_usDelayOptimize();



  cs1238_clk_h;
  PY_Delay_us_t(120); //soft reset cs1238
  cs1238_clk_l;
  PY_Delay_us_t(10);

  __HAL_UART_CLEAR_FLAG(&huart2, UART_FLAG_RXNE);
  HAL_UART_Receive_IT(&huart2, (uint8_t *)&cmd, 1);
  /* USER CODE END 2 */

  /* Infinite loop */
  /* USER CODE BEGIN WHILE */
  while (1)
  {

	  if(cmd==0x01) //read value w/o update info
		  {
			  while(cs1238_rdy) ;
		      while(!cs1238_rdy) ;
		      cs1238_data = 0;
			  PY_Delay_us_t(1);

			  for(uint8_t i=1;i<=24;i++)
			  {
				  cs1238_clk_h;
				  PY_Delay_us_t(1);
				  cs1238_clk_l;
				  cs1238_data |=  (((uint32_t)cs1238_dout)<<(24-i));
				  PY_Delay_us_t(1);
			  }

			  while( CDC_Transmit_FS(&cs1238_data, 3) != USBD_OK ) PY_Delay_us_t(1);

	  }
      else if(cmd==0x02) //read value w/ update info
	  {
		  /*
		   * Dout value from CLK 25 indicates Config register was written new value already
		   * Dout value from CLK 26 gets 0 always without meaning
		   */

		      while(cs1238_rdy) ;
		      while(!cs1238_rdy);
			  cs1238_data = 0;
			  PY_Delay_us_t(1);

			  /*clk 1~24*/
			  for(uint8_t i=1;i<=24;i++)
			  {
				  cs1238_clk_h;
				  PY_Delay_us_t(1);
				  cs1238_clk_l;
				  cs1238_data |=  (((uint32_t)cs1238_dout)<<(24-i));
				  PY_Delay_us_t(1);
			  }

			  /*clk 25*/
			  cs1238_clk_h;
			  PY_Delay_us_t(1);
			  cs1238_clk_l;
			  config_reg_update_status = cs1238_dout;
			  PY_Delay_us_t(1);

			  /*clk 26*/
			  cs1238_clk_h;
			  PY_Delay_us_t(1);
			  cs1238_clk_l;
			  PY_Delay_us_t(1);

			  /*clk 27*/
			  cs1238_clk_h;
			  Dout_PP_Mode();
			  PY_Delay_us_t(1);
			  cs1238_clk_l;
			  PY_Delay_us_t(1);
			  Dout_OD_Mode();

		  while( CDC_Transmit_FS(&cs1238_data, 3) != USBD_OK ) PY_Delay_us_t(1);
		  while( CDC_Transmit_FS(&config_reg_update_status, 1) != USBD_OK ) PY_Delay_us_t(1);

	  }
	  else if(cmd==0x03) //Read config register
	  {
	      cmd = 0x00;

		      while(cs1238_rdy) ;
		      while(!cs1238_rdy);
			  cs1238_data = 0;
			  PY_Delay_us_t(1);

			  /*clk 1~24*/
			  for(uint8_t i=1;i<=24;i++)
			  {
				  cs1238_clk_h;
				  PY_Delay_us_t(1);
				  cs1238_clk_l;
				  PY_Delay_us_t(1);
			  }

			  /*clk 25*/
			  cs1238_clk_h;
			  PY_Delay_us_t(1);
			  cs1238_clk_l;
			  PY_Delay_us_t(1);

			  /*clk 26*/
			  cs1238_clk_h;
			  PY_Delay_us_t(1);
			  cs1238_clk_l;
			  PY_Delay_us_t(1);

			  /*clk 27*/
			  cs1238_clk_h;
			  Dout_PP_Mode();
			  PY_Delay_us_t(1);
			  cs1238_clk_l;
			  PY_Delay_us_t(1);

			  /*clk 28*/
			  cs1238_clk_h;
			  PY_Delay_us_t(1);
			  cs1238_clk_l;
			  PY_Delay_us_t(1);

			  /*clk 29*/
			  cs1238_clk_h;
			  PY_Delay_us_t(1);
			  cs1238_clk_l;
			  PY_Delay_us_t(1);

			  /*clk 30~36*/
			  for(uint8_t i=1;i<8;i++)
			  {
					  cs1238_clk_h;
					  if(((RReg_CMD<<i)&0x80)) write_to_cs1238_dout_h;
					  else write_to_cs1238_dout_l;
					  PY_Delay_us_t(1);
					  cs1238_clk_l;
					  PY_Delay_us_t(1);
			  }

			  /*clk 37*/
			  Dout_OD_Mode();
			  cs1238_clk_h;
			  PY_Delay_us_t(1);
			  cs1238_clk_l;
			  PY_Delay_us_t(1);

			  /*clk 38~45*/
			  config_reg = 0;
			  for(uint8_t i=0;i<8;i++)
			  {
					  cs1238_clk_h;
					  PY_Delay_us_t(1);
					  cs1238_clk_l;
					  config_reg |=  (cs1238_dout<<(7-i));
					  PY_Delay_us_t(1);
			  }

			  /*clk 46*/
			  Dout_PP_Mode();
			  cs1238_clk_h;
			  PY_Delay_us_t(1);
			  cs1238_clk_l;
			  PY_Delay_us_t(1);
			  Dout_OD_Mode();


		  while( CDC_Transmit_FS(&config_reg, 1) != USBD_OK ) PY_Delay_us_t(1);

	  }
	  else if(cmd&0x80) //Set config register
	  {
		  config_reg = cmd&0x7F; //Config register value to be sent
	      while(cs1238_rdy) ;
	      while(!cs1238_rdy);
		  cs1238_data = 0;
		  PY_Delay_us_t(1);

		  /*clk 1~24*/
		  for(uint8_t i=1;i<=24;i++)
		  {
			  cs1238_clk_h;
			  PY_Delay_us_t(1);
			  cs1238_clk_l;
			  PY_Delay_us_t(1);
		  }

		  /*clk 25*/
		  cs1238_clk_h;
		  PY_Delay_us_t(1);
		  cs1238_clk_l;
		  PY_Delay_us_t(1);

		  /*clk 26*/
		  cs1238_clk_h;
		  PY_Delay_us_t(1);
		  cs1238_clk_l;
		  PY_Delay_us_t(1);

		  /*clk 27*/
		  cs1238_clk_h;
		  Dout_PP_Mode();
		  PY_Delay_us_t(1);
		  cs1238_clk_l;
		  PY_Delay_us_t(1);

		  /*clk 28*/
		  cs1238_clk_h;
		  PY_Delay_us_t(1);
		  cs1238_clk_l;
		  PY_Delay_us_t(1);

		  /*clk 29*/
		  cs1238_clk_h;
		  PY_Delay_us_t(1);
		  cs1238_clk_l;
		  PY_Delay_us_t(1);

		  /*clk 30~36*/
		  for(uint8_t i=1;i<8;i++)
		  {
				  cs1238_clk_h;
				  if(((WReg_CMD<<i)&0x80)) write_to_cs1238_dout_h;
				  else write_to_cs1238_dout_l;
				  PY_Delay_us_t(1);
				  cs1238_clk_l;
				  PY_Delay_us_t(1);
		  }

		  /*clk 37*/
		  Dout_PP_Mode();
		  cs1238_clk_h;
		  PY_Delay_us_t(1);
		  cs1238_clk_l;
		  PY_Delay_us_t(1);

		  /*clk 38~45*/
		  for(uint8_t i=0;i<8;i++)
		  {
				  cs1238_clk_h;
				  if(((config_reg<<i)&0x80)) write_to_cs1238_dout_h;
				  else write_to_cs1238_dout_l;
				  PY_Delay_us_t(1);
				  cs1238_clk_l;
				  PY_Delay_us_t(1);
		  }

		  /*clk 46*/
		  Dout_PP_Mode();
		  cs1238_clk_h;
		  PY_Delay_us_t(1);
		  cs1238_clk_l;
		  PY_Delay_us_t(1);
		  Dout_OD_Mode();


	  while( CDC_Transmit_FS(&config_reg, 1) != USBD_OK ) PY_Delay_us_t(1);
	  cmd = 0;

	  }
	  else;


	  PY_Delay_us_t(500000);

    /* USER CODE END WHILE */

    /* USER CODE BEGIN 3 */
  }
  /* USER CODE END 3 */
}

/**
  * @brief System Clock Configuration
  * @retval None
  */
void SystemClock_Config(void)
{
  RCC_OscInitTypeDef RCC_OscInitStruct = {0};
  RCC_ClkInitTypeDef RCC_ClkInitStruct = {0};
  RCC_PeriphCLKInitTypeDef PeriphClkInit = {0};

  /** Initializes the RCC Oscillators according to the specified parameters
  * in the RCC_OscInitTypeDef structure.
  */
  RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_HSE;
  RCC_OscInitStruct.HSEState = RCC_HSE_ON;
  RCC_OscInitStruct.HSEPredivValue = RCC_HSE_PREDIV_DIV1;
  RCC_OscInitStruct.HSIState = RCC_HSI_ON;
  RCC_OscInitStruct.PLL.PLLState = RCC_PLL_ON;
  RCC_OscInitStruct.PLL.PLLSource = RCC_PLLSOURCE_HSE;
  RCC_OscInitStruct.PLL.PLLMUL = RCC_PLL_MUL9;
  if (HAL_RCC_OscConfig(&RCC_OscInitStruct) != HAL_OK)
  {
    Error_Handler();
  }

  /** Initializes the CPU, AHB and APB buses clocks
  */
  RCC_ClkInitStruct.ClockType = RCC_CLOCKTYPE_HCLK|RCC_CLOCKTYPE_SYSCLK
                              |RCC_CLOCKTYPE_PCLK1|RCC_CLOCKTYPE_PCLK2;
  RCC_ClkInitStruct.SYSCLKSource = RCC_SYSCLKSOURCE_PLLCLK;
  RCC_ClkInitStruct.AHBCLKDivider = RCC_SYSCLK_DIV1;
  RCC_ClkInitStruct.APB1CLKDivider = RCC_HCLK_DIV2;
  RCC_ClkInitStruct.APB2CLKDivider = RCC_HCLK_DIV1;

  if (HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_2) != HAL_OK)
  {
    Error_Handler();
  }
  PeriphClkInit.PeriphClockSelection = RCC_PERIPHCLK_USB;
  PeriphClkInit.UsbClockSelection = RCC_USBCLKSOURCE_PLL_DIV1_5;
  if (HAL_RCCEx_PeriphCLKConfig(&PeriphClkInit) != HAL_OK)
  {
    Error_Handler();
  }
}

/**
  * @brief USART2 Initialization Function
  * @param None
  * @retval None
  */
static void MX_USART2_UART_Init(void)
{

  /* USER CODE BEGIN USART2_Init 0 */

  /* USER CODE END USART2_Init 0 */

  /* USER CODE BEGIN USART2_Init 1 */

  /* USER CODE END USART2_Init 1 */
  huart2.Instance = USART2;
  huart2.Init.BaudRate = 115200;
  huart2.Init.WordLength = UART_WORDLENGTH_8B;
  huart2.Init.StopBits = UART_STOPBITS_1;
  huart2.Init.Parity = UART_PARITY_NONE;
  huart2.Init.Mode = UART_MODE_TX_RX;
  huart2.Init.HwFlowCtl = UART_HWCONTROL_NONE;
  huart2.Init.OverSampling = UART_OVERSAMPLING_16;
  if (HAL_UART_Init(&huart2) != HAL_OK)
  {
    Error_Handler();
  }
  /* USER CODE BEGIN USART2_Init 2 */

  /* USER CODE END USART2_Init 2 */

}

/**
  * @brief GPIO Initialization Function
  * @param None
  * @retval None
  */
static void MX_GPIO_Init(void)
{
  GPIO_InitTypeDef GPIO_InitStruct = {0};

  /* GPIO Ports Clock Enable */
  __HAL_RCC_GPIOD_CLK_ENABLE();
  __HAL_RCC_GPIOA_CLK_ENABLE();
  __HAL_RCC_GPIOB_CLK_ENABLE();

  /*Configure GPIO pin Output Level */
  HAL_GPIO_WritePin(GPIOB, GPIO_PIN_0, GPIO_PIN_RESET);

  /*Configure GPIO pin Output Level */
  HAL_GPIO_WritePin(GPIOB, GPIO_PIN_1, GPIO_PIN_SET);

  /*Configure GPIO pin : PB0 */
  GPIO_InitStruct.Pin = GPIO_PIN_0;
  GPIO_InitStruct.Mode = GPIO_MODE_OUTPUT_PP;
  GPIO_InitStruct.Pull = GPIO_NOPULL;
  GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_HIGH;
  HAL_GPIO_Init(GPIOB, &GPIO_InitStruct);

  /*Configure GPIO pin : PB1 */
  GPIO_InitStruct.Pin = GPIO_PIN_1;
  GPIO_InitStruct.Mode = GPIO_MODE_OUTPUT_OD;
  GPIO_InitStruct.Pull = GPIO_PULLUP;
  GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_HIGH;
  HAL_GPIO_Init(GPIOB, &GPIO_InitStruct);

}

/* USER CODE BEGIN 4 */
void Dout_OD_Mode(void)
{
  GPIO_InitTypeDef GPIO_InitStruct = {0};

  /* GPIO Ports Clock Enable */
  __HAL_RCC_GPIOB_CLK_ENABLE();

  /*Configure GPIO pin Output Level */
  HAL_GPIO_WritePin(GPIOB, GPIO_PIN_1, GPIO_PIN_SET);

  /*Configure GPIO pin : PB1 */
  GPIO_InitStruct.Pin = GPIO_PIN_1;
  GPIO_InitStruct.Mode = GPIO_MODE_OUTPUT_OD;
  GPIO_InitStruct.Pull = GPIO_PULLUP;
  GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_HIGH;
  HAL_GPIO_Init(GPIOB, &GPIO_InitStruct);

}

void Dout_PP_Mode(void)
{
  GPIO_InitTypeDef GPIO_InitStruct = {0};

  /* GPIO Ports Clock Enable */
  __HAL_RCC_GPIOB_CLK_ENABLE();

  /*Configure GPIO pin Output Level */
  HAL_GPIO_WritePin(GPIOB, GPIO_PIN_1, GPIO_PIN_SET);

  /*Configure GPIO pin : PB1 */
  GPIO_InitStruct.Pin = GPIO_PIN_1;
  GPIO_InitStruct.Mode = GPIO_MODE_OUTPUT_PP;
  GPIO_InitStruct.Pull = GPIO_NOPULL;
  GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_HIGH;
  HAL_GPIO_Init(GPIOB, &GPIO_InitStruct);

}

void HAL_UART_RxCpltCallback(UART_HandleTypeDef *UartHandle)
{
	HAL_UART_Receive_IT(&huart2, (uint8_t *)&cmd, 1);
}
/* USER CODE END 4 */

/**
  * @brief  This function is executed in case of error occurrence.
  * @retval None
  */
void Error_Handler(void)
{
  /* USER CODE BEGIN Error_Handler_Debug */
  /* User can add his own implementation to report the HAL error return state */
  __disable_irq();
  while (1)
  {
  }
  /* USER CODE END Error_Handler_Debug */
}

#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
  * @retval None
  */
void assert_failed(uint8_t *file, uint32_t line)
{
  /* USER CODE BEGIN 6 */
  /* User can add his own implementation to report the file name and line number,
     ex: printf("Wrong parameters value: file %s on line %drn", file, line) */
  /* USER CODE END 6 */
}
#endif /* USE_FULL_ASSERT */

STM32代码测试

通过串口工具发送0x01指令（只读取24位ADC值, 观察工具左侧接收的24位16进制数据）：
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通过串口工具发送0x02指令（读取24位ADC值和寄存器更新状态信息, 观察工具左侧接收的32位16进制数据）：

在这里插入图片描述

通过串口工具发送0x03指令（读配置寄存器数据）：
在这里插入图片描述
通过串口工具发送0x8d指令（配置寄存器设置为0x0D, 选择采样通道B）：

回读, 发送0x03指令（读配置寄存器数据）：

温度数据可根据手册说明进行设置读取解析。

代码实现十进制数据输出，如果要切换为串口printf打印输出，可以参考：
STM32 UART串口printf函数应用及浮点打印代码空间节省 (HAL)

CS1238 5V供电与STM32 3.3V供电连接方式

可采用如下方案，实现CS1238 5V供电与STM32 3.3V供电连接方式。STM32选用FT（5V耐压）的GPIO，三个GPIO都设置成Open-drain无上下拉输出模式。

第一个GPIO连接外部1K上拉到5V，控制输出时钟给CS1239。
第二个GPIO通过PNP或者PMOS管电路，GPIO输出逻辑1时，5V电压不输出，GPIO输出逻辑0时，5V电压输出。从而实现控制向DOUT输出直驱高电平。
第三个GPIO始终输出逻辑1（高阻态），并用作DOUT状态值读取。
在这里插入图片描述