STM32模拟I2C获取AP3216C光学接近传感器数据
STM32模拟I2C获取AP3216C光学接近传感器数据
AP3216C是一款三合一的光学传感器。这块传感器集成了光强传感器(ALS: AmbientLight Sensor),接近传感器(PS: Proximity Sensor),还有一个红外LED(Infrared LED)。
这款光学传感器可以单独进行环境光的检测,单独进行红外环境光的检测,以及通过自带LED的发光进行接近距离的检测。也支持进行交替检测。在具体的应用模式上有连续性检测模式和单次检测模式。由于有比较好的性价比,可以用在灰度检测,循迹等场景,多颗配合还可以实现手势检测。
AP3216C传感器的体积较小,做成模块体积也不大,能够应用在空间小的环境实现光学强度检测,且具有对弱反光环境的检测能力,具有日常交流噪声的抑制能力,具有温度补偿能力及LED发光强度4级可调。
这里以STM32F401CCU6为例, 采用STM32CUBEIDE开发环境,实现AP3216C的控制和数据获取。
STM32工程配置
首先建立工程并配置时钟:
配置两个GPIO用于模拟I2C, 采用Open Drain配置方式:
这里采用USB串口的方式输出数据,所以例化USB端口为Virtual Port,采用默认参数即可:
保存并生成初始工程代码:
STM32模拟I2C代码
实现模拟I2C协议需要用到微秒级延时函数,采用 STM32 HAL us delay(微秒延时)的指令延时实现方式及优化 里的函数实现。
#define us_num 10#define SCL_OUT_H HAL_GPIO_WritePin(GPIOB, GPIO_PIN_6, GPIO_PIN_SET)
#define SCL_OUT_L HAL_GPIO_WritePin(GPIOB, GPIO_PIN_6, GPIO_PIN_RESET)
#define SDA_OUT_H HAL_GPIO_WritePin(GPIOB, GPIO_PIN_7, GPIO_PIN_SET)
#define SDA_OUT_L HAL_GPIO_WritePin(GPIOB, GPIO_PIN_7, GPIO_PIN_RESET)
#define SDA_IN HAL_GPIO_ReadPin(GPIOB, GPIO_PIN_7)void I2C_Init(void)
{SDA_OUT_H;SCL_OUT_H;PY_Delay_us_t(1000000) ;
}void I2C_Start(void)
{PY_Delay_us_t(us_num) ;SDA_OUT_H;SCL_OUT_H;PY_Delay_us_t(us_num/2) ;SDA_OUT_L;PY_Delay_us_t(us_num/2) ;SCL_OUT_L;
}void I2C_Stop(void)
{SCL_OUT_L;PY_Delay_us_t(us_num) ;SDA_OUT_L;PY_Delay_us_t(us_num) ;SCL_OUT_H;PY_Delay_us_t(us_num) ;SDA_OUT_H;PY_Delay_us_t(us_num) ;
}void I2C_Write_Ack(void)
{PY_Delay_us_t(us_num/2) ;SDA_OUT_L;PY_Delay_us_t(us_num/2) ;SCL_OUT_H;PY_Delay_us_t(us_num) ;SCL_OUT_L;SDA_OUT_H;}uint8_t I2C_Read_Ack(void)
{uint8_t status=0;SCL_OUT_L;PY_Delay_us_t(us_num/2) ;SDA_OUT_H;PY_Delay_us_t(us_num/2) ;status = SDA_IN;SCL_OUT_H;PY_Delay_us_t(us_num) ;SCL_OUT_L;SDA_OUT_L;return status;}void I2C_Send_Byte(uint8_t txd)
{for(uint8_t i=0;i<8;i++){PY_Delay_us_t(us_num/2) ;if((txd&0x80)>>7) SDA_OUT_H;else SDA_OUT_L;txd<<=1;PY_Delay_us_t(us_num/2) ;SCL_OUT_H;PY_Delay_us_t(us_num) ;SCL_OUT_L;}SDA_OUT_L;
}uint8_t I2C_Read_Byte(unsigned char rdack)
{uint8_t rxd=0;for(uint8_t i=0;i<8;i++ ){SCL_OUT_L;PY_Delay_us_t(us_num/2) ;SDA_OUT_H;PY_Delay_us_t(us_num/2) ;SCL_OUT_H;rxd<<=1;if(SDA_IN) rxd++;PY_Delay_us_t(us_num) ;}SCL_OUT_L;SDA_OUT_H;if (rdack) I2C_Write_Ack();return rxd;
}void AP3216_WRITE( uint8_t WrAddr, uint8_t data)
{uint8_t daddr = 0x3c; //AP3216 device address (0x1e<<1)I2C_Start();I2C_Send_Byte(daddr);I2C_Read_Ack();I2C_Send_Byte(WrAddr);I2C_Read_Ack();I2C_Send_Byte(data);I2C_Read_Ack();I2C_Stop();}uint8_t AP3216_READ( uint8_t RdAddr)
{uint8_t RegValue = 0;uint8_t daddr = 0x3c; //AP3216 device address (0x1e<<1)I2C_Start();I2C_Send_Byte(daddr);I2C_Read_Ack();I2C_Send_Byte(RdAddr);I2C_Read_Ack();I2C_Start();I2C_Send_Byte(daddr+1);I2C_Read_Ack();RegValue=I2C_Read_Byte(0);I2C_Stop();return RegValue;
}
STM32完整工程代码
这里实现的完整工程代码,通过预定义参数控制实现环境白光(ALS),环境红外光(IR),接近反光(PS)的其中一种检测,而其它的各种方式以及中断实现方式,都可以在此协议访问基础上进行扩展实现。
#define DMODE 0 //Detecting mode for AP3216. 0: ALS read only; 1: IR read only; 2: PS read only; ......
需要注意的是,环境红外光和接近反光(PS+IR)是集成在一个检测部分,因此是同时使能,在做环境红外光检测时,配置接近反光的LED为关闭状态。另外,在做接近反光检测时,环境红外光检测也是在工作,此时实际上一个检测周期是如下的概念:
在PS检测前进行IR检测的目的是对环境红外噪光强度进行识别,以利于判断后面PS检测的有效性。
完整的工程实现代码如下:
/* 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.********************************************************************************/
/* USER CODE END Header */
/* Includes ------------------------------------------------------------------*/
#include "main.h"
#include "usb_device.h"/* Private includes ----------------------------------------------------------*/
/* USER CODE BEGIN Includes */
#define DMODE 0 //Detecting mode for AP3216. 0: ALS read only; 1: IR read only; 2: PS read only; ......
/* 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++;
}#define us_num 10#define SCL_OUT_H HAL_GPIO_WritePin(GPIOB, GPIO_PIN_6, GPIO_PIN_SET)
#define SCL_OUT_L HAL_GPIO_WritePin(GPIOB, GPIO_PIN_6, GPIO_PIN_RESET)
#define SDA_OUT_H HAL_GPIO_WritePin(GPIOB, GPIO_PIN_7, GPIO_PIN_SET)
#define SDA_OUT_L HAL_GPIO_WritePin(GPIOB, GPIO_PIN_7, GPIO_PIN_RESET)
#define SDA_IN HAL_GPIO_ReadPin(GPIOB, GPIO_PIN_7)void I2C_Init(void)
{SDA_OUT_H;SCL_OUT_H;PY_Delay_us_t(1000000) ;
}void I2C_Start(void)
{PY_Delay_us_t(us_num) ;SDA_OUT_H;SCL_OUT_H;PY_Delay_us_t(us_num/2) ;SDA_OUT_L;PY_Delay_us_t(us_num/2) ;SCL_OUT_L;
}void I2C_Stop(void)
{SCL_OUT_L;PY_Delay_us_t(us_num) ;SDA_OUT_L;PY_Delay_us_t(us_num) ;SCL_OUT_H;PY_Delay_us_t(us_num) ;SDA_OUT_H;PY_Delay_us_t(us_num) ;
}void I2C_Write_Ack(void)
{PY_Delay_us_t(us_num/2) ;SDA_OUT_L;PY_Delay_us_t(us_num/2) ;SCL_OUT_H;PY_Delay_us_t(us_num) ;SCL_OUT_L;SDA_OUT_H;}uint8_t I2C_Read_Ack(void)
{uint8_t status=0;SCL_OUT_L;PY_Delay_us_t(us_num/2) ;SDA_OUT_H;PY_Delay_us_t(us_num/2) ;status = SDA_IN;SCL_OUT_H;PY_Delay_us_t(us_num) ;SCL_OUT_L;SDA_OUT_L;return status;}void I2C_Send_Byte(uint8_t txd)
{for(uint8_t i=0;i<8;i++){PY_Delay_us_t(us_num/2) ;if((txd&0x80)>>7) SDA_OUT_H;else SDA_OUT_L;txd<<=1;PY_Delay_us_t(us_num/2) ;SCL_OUT_H;PY_Delay_us_t(us_num) ;SCL_OUT_L;}SDA_OUT_L;
}uint8_t I2C_Read_Byte(unsigned char rdack)
{uint8_t rxd=0;for(uint8_t i=0;i<8;i++ ){SCL_OUT_L;PY_Delay_us_t(us_num/2) ;SDA_OUT_H;PY_Delay_us_t(us_num/2) ;SCL_OUT_H;rxd<<=1;if(SDA_IN) rxd++;PY_Delay_us_t(us_num) ;}SCL_OUT_L;SDA_OUT_H;if (rdack) I2C_Write_Ack();return rxd;
}void AP3216_WRITE( uint8_t WrAddr, uint8_t data)
{uint8_t daddr = 0x3c; //AP3216 device address (0x1e<<1)I2C_Start();I2C_Send_Byte(daddr);I2C_Read_Ack();I2C_Send_Byte(WrAddr);I2C_Read_Ack();I2C_Send_Byte(data);I2C_Read_Ack();I2C_Stop();}uint8_t AP3216_READ( uint8_t RdAddr)
{uint8_t RegValue = 0;uint8_t daddr = 0x3c; //AP3216 device address (0x1e<<1)I2C_Start();I2C_Send_Byte(daddr);I2C_Read_Ack();I2C_Send_Byte(RdAddr);I2C_Read_Ack();I2C_Start();I2C_Send_Byte(daddr+1);I2C_Read_Ack();RegValue=I2C_Read_Byte(0);I2C_Stop();return RegValue;
}
/* USER CODE END PTD *//* Private define ------------------------------------------------------------*/
/* USER CODE BEGIN PD */
/* USER CODE END PD *//* Private macro -------------------------------------------------------------*/
/* USER CODE BEGIN PM */
uint8_t rdata[3];
/* 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();MX_USB_DEVICE_Init();/* USER CODE BEGIN 2 */PY_usDelayTest();PY_usDelayOptimize();I2C_Init();/** 000: Power down (Default)* 001: ALS function active* 010: PS+IR function active. The IR DATA can show the intensity of environment IR.* 011: ALS and PS+IR functions active. The device will operate the ALS and PS+IR function alternately.* 100: SW reset* 101: ALS function once* 110: PS+IR function once* 111: ALS and PS+IR functions once*/AP3216_WRITE(0x00, 0x00);PY_Delay_us_t(100000);if(DMODE==0){//ALS Read OnlyAP3216_WRITE(0x00, 0x01); //ALS modePY_Delay_us_t(100000);AP3216_WRITE(0x10, 0x10); //ResolutionPY_Delay_us_t(100000);AP3216_WRITE(0x19, 0x40); //Loss calibrationPY_Delay_us_t(100000);rdata[2]=0xff;while(1){__disable_irq();rdata[0]= AP3216_READ(0x0c);rdata[1] = AP3216_READ(0x0d);__enable_irq();CDC_Transmit_FS(rdata, 3);PY_Delay_us_t(1000000);}}if(DMODE==1){//IR Read OnlyAP3216_WRITE(0x00, 0x02);PY_Delay_us_t(100000);AP3216_WRITE(0x20, 0x05); //PS config: defaultPY_Delay_us_t(100000);AP3216_WRITE(0x21, 0x03); //Close LED pulsePY_Delay_us_t(100000);AP3216_WRITE(0x23, 0x00); //T(PS mean time) config: defaultPY_Delay_us_t(100000);AP3216_WRITE(0x24, 0x00); //PS LED waiting time: defaultPY_Delay_us_t(100000);rdata[2]=0xff;while(1){__disable_irq();rdata[0]= AP3216_READ(0x0A);if((rdata[0]>>7)>0){rdata[0]=0xff;rdata[1]=0xff;}else{rdata[1] = AP3216_READ(0x0B);rdata[0] = (rdata[0]&0x3)|(rdata[1]<<2);rdata[1] >>= 6;}__enable_irq();CDC_Transmit_FS(rdata, 3);PY_Delay_us_t(100000);}}if(DMODE==2){//PS Read OnlyAP3216_WRITE(0x00, 0x02);PY_Delay_us_t(100000);AP3216_WRITE(0x20, 0x05); //PS config: defaultPY_Delay_us_t(100000);AP3216_WRITE(0x21, 0x13); //LED pulse and driving current strengthPY_Delay_us_t(100000);AP3216_WRITE(0x23, 0x00); //T(PS mean time) config: defaultPY_Delay_us_t(100000);AP3216_WRITE(0x24, 0x00); //PS LED waiting time: defaultPY_Delay_us_t(100000);AP3216_WRITE(0x28, 0x00); PY_Delay_us_t(100000);AP3216_WRITE(0x29, 0x00);//PS CalibrationPY_Delay_us_t(100000);rdata[2]=0xff;while(1){__disable_irq();rdata[0]= AP3216_READ(0x0E);if((rdata[0]&0x40)>0){rdata[0]=0xff;rdata[1]=0xff;}else{rdata[1] = AP3216_READ(0x0F)&0x3F;rdata[0] = (rdata[0]&0x0F)|(rdata[1]<<4);rdata[1] >>= 4;}__enable_irq();CDC_Transmit_FS(rdata, 3);PY_Delay_us_t(100000);}}/* USER CODE END 2 *//* Infinite loop *//* USER CODE BEGIN WHILE */while (1){PY_Delay_us(1000000);/* 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_HSE;RCC_OscInitStruct.HSEState = RCC_HSE_ON;RCC_OscInitStruct.PLL.PLLState = RCC_PLL_ON;RCC_OscInitStruct.PLL.PLLSource = RCC_PLLSOURCE_HSE;RCC_OscInitStruct.PLL.PLLM = 25;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};/* GPIO Ports Clock Enable */__HAL_RCC_GPIOH_CLK_ENABLE();__HAL_RCC_GPIOA_CLK_ENABLE();__HAL_RCC_GPIOB_CLK_ENABLE();/*Configure GPIO pin Output Level */HAL_GPIO_WritePin(GPIOB, GPIO_PIN_6|GPIO_PIN_7, GPIO_PIN_SET);/*Configure GPIO pins : PB6 PB7 */GPIO_InitStruct.Pin = GPIO_PIN_6|GPIO_PIN_7;GPIO_InitStruct.Mode = GPIO_MODE_OUTPUT_OD;GPIO_InitStruct.Pull = GPIO_PULLUP;GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_VERY_HIGH;HAL_GPIO_Init(GPIOB, &GPIO_InitStruct);}/* 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
采用无操作系统USB串口输出的例程下载
采用RT-THREAD NANO操作系统的普通串口输出的例程下载
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