STM32模拟SPI协议控制数字电位器MCP41010电阻值
MCP41010是单路8位分辨率数字电位器,通过SPI接口可控制电位器阻值分配,相当于PW0端在PA0和PB0之间滑动。如下图所示:
MCP41010是10K欧姆规格的数字电位器,即PA0和PB0之间的阻值恒定为10K,PW0与PA0或PW0与PB0之间的阻值互补可配。
另外有相关型号不同阻值规格和集成双路的MCP系列数字电位器,其控制原理相同:
这里介绍STM32模拟SPI协议控制数字电位器MCP41010的代码范例。采用STM32CUBEIDE开发平台,以STM32F401RCT6为例。
STM32工程配置
首先建立基本工程并设置时钟:
采用内部时钟源即可:
配置3个GPIO作为模拟SPI的管脚:
保存并生成初始工程代码:
STM32工程代码
代码里用到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
代码的实现功能为每隔5秒将阻值从低值,中值和高值进行转变,用万用表即可测试阻值验证。
建立MCP41010.h头文件:
#ifndef INC_MCP41010_H_
#define INC_MCP41010_H_
#include "main.h"
void PY_Delay_us_t(uint32_t Delay);
void MCP41010_Init(void);
void MCP41010_SHUTDONW(void);
void MCP41010_Write(uint8_t data);
#endif /* INC_MCP41010_H_ */
建立MCP41010.c源文件:
#include "MCP41010.h"
#define MCP41010_CS_L HAL_GPIO_WritePin(GPIOB, GPIO_PIN_0, GPIO_PIN_RESET)
#define MCP4101_CS_H HAL_GPIO_WritePin(GPIOB, GPIO_PIN_0, GPIO_PIN_SET)
#define MCP4101_SCK_L HAL_GPIO_WritePin(GPIOB, GPIO_PIN_1, GPIO_PIN_RESET)
#define MCP4101_SCK_H HAL_GPIO_WritePin(GPIOB, GPIO_PIN_1, GPIO_PIN_SET)
#define MCP4101_SI_L HAL_GPIO_WritePin(GPIOB, GPIO_PIN_2, GPIO_PIN_RESET)
#define MCP4101_SI_H HAL_GPIO_WritePin(GPIOB, GPIO_PIN_2, GPIO_PIN_SET)
#define SPI_Delay_us 2
void MCP41010_Init(void)
{
MCP4101_CS_H;
}
void MCP41010_SHUTDONW(void)
{
uint16_t MD=0x2100;
MCP41010_CS_L;PY_Delay_us_t(SPI_Delay_us);
for(uint8_t i=0;i<16;i++)
{
MCP4101_SCK_L;
if(MD&0x8000){MCP4101_SI_H;}
else {MCP4101_SI_L;}
PY_Delay_us_t(SPI_Delay_us);
MCP4101_SCK_H;
MD<<=1;
PY_Delay_us_t(SPI_Delay_us);
}
MCP4101_SCK_L;
PY_Delay_us_t(SPI_Delay_us);
MCP4101_CS_H ;
}
void MCP41010_Write(uint8_t data)
{
uint16_t MD=0x1100;
MD |= data;
MCP41010_CS_L;PY_Delay_us_t(SPI_Delay_us);
for(uint8_t i=0;i<16;i++)
{
MCP4101_SCK_L;
if(MD&0x8000){MCP4101_SI_H;}
else {MCP4101_SI_L;}
PY_Delay_us_t(SPI_Delay_us);
MCP4101_SCK_H;
MD<<=1;
PY_Delay_us_t(SPI_Delay_us);
}
MCP4101_SCK_L;
PY_Delay_us_t(SPI_Delay_us);
MCP4101_CS_H ;
}
main.c文件里实现测试功能:
/* USER CODE BEGIN Header */
/**
******************************************************************************
* @file : main.c
* @brief : Main program body
******************************************************************************
* @attention
*
* Copyright (c) 2023 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.
*
******************************************************************************
*/
/* USER CODE END Header */
/* Includes ------------------------------------------------------------------*/
#include "main.h"
/* Private includes ----------------------------------------------------------*/
/* USER CODE BEGIN Includes */
#include "MCP41010.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 */
/* USER CODE END PD */
/* Private macro -------------------------------------------------------------*/
/* USER CODE BEGIN PM */
/* USER CODE END PM */
/* Private variables ---------------------------------------------------------*/
/* USER CODE BEGIN PV */
/* USER CODE END PV */
/* Private function prototypes -----------------------------------------------*/
void SystemClock_Config(void);
static void MX_GPIO_Init(void);
/* USER CODE BEGIN PFP */
/* USER CODE END PFP */
/* Private user code ---------------------------------------------------------*/
/* USER CODE BEGIN 0 */
/* USER CODE END 0 */
/**
* @brief The application entry point.
* @retval int
*/
int main(void)
{
/* USER CODE BEGIN 1 */
/* 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();
/* USER CODE BEGIN 2 */
PY_usDelayTest();
PY_usDelayOptimize();
MCP41010_Init();
/* USER CODE END 2 */
/* Infinite loop */
/* USER CODE BEGIN WHILE */
while (1)
{
MCP41010_Write(0x01);
PY_Delay_us_t(5000000);
MCP41010_Write(0x80);
PY_Delay_us_t(5000000);
MCP41010_Write(0xFF);
PY_Delay_us_t(5000000);
/* 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};
/** Configure the main internal regulator output voltage
*/
__HAL_RCC_PWR_CLK_ENABLE();
__HAL_PWR_VOLTAGESCALING_CONFIG(PWR_REGULATOR_VOLTAGE_SCALE2);
/** Initializes the RCC Oscillators according to the specified parameters
* in the RCC_OscInitTypeDef structure.
*/
RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_HSI;
RCC_OscInitStruct.HSIState = RCC_HSI_ON;
RCC_OscInitStruct.HSICalibrationValue = RCC_HSICALIBRATION_DEFAULT;
RCC_OscInitStruct.PLL.PLLState = RCC_PLL_ON;
RCC_OscInitStruct.PLL.PLLSource = RCC_PLLSOURCE_HSI;
RCC_OscInitStruct.PLL.PLLM = 16;
RCC_OscInitStruct.PLL.PLLN = 336;
RCC_OscInitStruct.PLL.PLLP = RCC_PLLP_DIV4;
RCC_OscInitStruct.PLL.PLLQ = 7;
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();
}
}
/**
* @brief GPIO Initialization Function
* @param None
* @retval None
*/
static void MX_GPIO_Init(void)
{
GPIO_InitTypeDef GPIO_InitStruct = {0};
/* USER CODE BEGIN MX_GPIO_Init_1 */
/* USER CODE END MX_GPIO_Init_1 */
/* GPIO Ports Clock Enable */
__HAL_RCC_GPIOB_CLK_ENABLE();
/*Configure GPIO pin Output Level */
HAL_GPIO_WritePin(GPIOB, GPIO_PIN_0, GPIO_PIN_SET);
/*Configure GPIO pin Output Level */
HAL_GPIO_WritePin(GPIOB, GPIO_PIN_1|GPIO_PIN_2, GPIO_PIN_RESET);
/*Configure GPIO pins : PB0 PB1 PB2 */
GPIO_InitStruct.Pin = GPIO_PIN_0|GPIO_PIN_1|GPIO_PIN_2;
GPIO_InitStruct.Mode = GPIO_MODE_OUTPUT_PP;
GPIO_InitStruct.Pull = GPIO_NOPULL;
GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_VERY_HIGH;
HAL_GPIO_Init(GPIOB, &GPIO_InitStruct);
/* USER CODE BEGIN MX_GPIO_Init_2 */
/* USER CODE END MX_GPIO_Init_2 */
}
/* USER CODE BEGIN 4 */
/* 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 %d\r\n", file, line) */
/* USER CODE END 6 */
}
#endif /* USE_FULL_ASSERT */
STM32例程下载
STM32F401模拟SPI协议控制数字电位器MCP41010电阻值例程
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