EC11编码器编码使用

文章目录

前要
原理
- 脉冲与定位
- 功能
- 硬件设计
编程
- 轮询模式
- 定时器Encoder模式
结束语

前要

关于EC11编码器的了解可以参考两篇文章，比较详细，在此就不多介绍了：

一篇文章带你了解——EC11编码器（关于硬件、原理图、上下拉等都有讲）
认识EC11旋转编码器&编写驱动程序

原理

脉冲与定位

15脉冲/30定位：每拨动一格，两个电平都相继翻转，是半个脉冲；再拨动一格，电平再相继翻转，也是半个脉冲；两个半脉冲形成一个完整脉冲。静止状态下，两个电平相同，都为高或低
20脉冲/20定位：每拨动一格，形成一个完整脉冲
对应下图如下：

示波器抓取部分波形：

(note: 两个脉冲跳变的间隔约为几十ms)

功能

通过2个pin负责编码器的波形检测，顺时针与逆时针波形不同

硬件设计

IO外部上拉与无上拉
在这里插入图片描述

编程

硬件条件：

MCU: stm32f407
编码器类型： EC11-15脉冲/30定位
连接： IO外部无上拉，设置MCU GPIO的内部上拉

下面使用两种方法来对编码器进行计数和使用。

轮询模式

直接就上代码了，随意两个GPIO

//GPIO初始化
void MX_GPIO_Init(void)
{GPIO_InitTypeDef GPIO_InitStruct = {0};/* GPIO Ports Clock Enable */__HAL_RCC_GPIOC_CLK_ENABLE();__HAL_RCC_GPIOH_CLK_ENABLE();__HAL_RCC_GPIOA_CLK_ENABLE();__HAL_RCC_GPIOB_CLK_ENABLE();/*Configure GPIO pin : PB6 */GPIO_InitStruct.Pin = GPIO_PIN_6;GPIO_InitStruct.Mode = GPIO_MODE_INPUT;GPIO_InitStruct.Pull = GPIO_PULLUP;HAL_GPIO_Init(GPIOB, &GPIO_InitStruct);/*Configure GPIO pin : PB7 */GPIO_InitStruct.Pin = GPIO_PIN_7;GPIO_InitStruct.Mode = GPIO_MODE_INPUT;GPIO_InitStruct.Pull = GPIO_PULLUP;HAL_GPIO_Init(GPIOB, &GPIO_InitStruct);}//判断检测
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_USART1_UART_Init();/* USER CODE BEGIN 2 */// exit_init();/* USER CODE END 2 *//* Infinite loop *//* USER CODE BEGIN WHILE */uint32_t count = 0;uint32_t wait_t = 0;bool encoder_switch = 0;uint8_t encoder_a_pre = HAL_GPIO_ReadPin(GPIOB, GPIO_PIN_6);// uint8_t encoder_b_pre = HAL_GPIO_ReadPin(GPIOB, GPIO_PIN_7);int32_t steps = 0;while (1){/* USER CODE END WHILE *//* USER CODE BEGIN 3 */uint32_t t = HAL_GetTick();uint8_t encoder_a = HAL_GPIO_ReadPin(GPIOB, GPIO_PIN_6);uint8_t encoder_b = HAL_GPIO_ReadPin(GPIOB, GPIO_PIN_7);if (encoder_a_pre != encoder_a && !encoder_switch) {wait_t = HAL_GetTick();encoder_switch = true;}if (encoder_switch && ((t - wait_t) >= 2 )) {//a 0->1, b 0 Clockwise; b 1 AntiClockwiseif (encoder_a == 1) {if (encoder_b == 0) {steps++;} else {steps--;}}//a 1->0, b 1 Clockwise; b 0 AntiClockwise else {if (encoder_b == 1) {steps++;} else {steps--;}}encoder_switch = false;encoder_a_pre = encoder_a;printf("%d\r\n", steps);}}/* USER CODE END 3 */
}

注意点：编码器电平发生变化时可能存在噪声，类似按键一样需要增加延时防抖，并且考虑到在系统中少加入延时死等这些不友善的代码，所以代码中有如上处理。

定时器Encoder模式

stm32中定时器有自带Encoder的功能，所以可以借助定时器的这个特性来实现我们的需求。
直接撸代码，GPIO必须使用复用功能有定时器的pin。

//定时器及IO初始化
TIM_HandleTypeDef htim4;/* TIM4 init function */
void MX_TIM4_Init(void)
{/* USER CODE BEGIN TIM4_Init 0 *//* USER CODE END TIM4_Init 0 */TIM_Encoder_InitTypeDef sConfig = {0};TIM_MasterConfigTypeDef sMasterConfig = {0};/* USER CODE BEGIN TIM4_Init 1 *//* USER CODE END TIM4_Init 1 */htim4.Instance = TIM4;htim4.Init.Prescaler = 0;htim4.Init.CounterMode = TIM_COUNTERMODE_UP;htim4.Init.Period = 65535;htim4.Init.ClockDivision = TIM_CLOCKDIVISION_DIV1;htim4.Init.AutoReloadPreload = TIM_AUTORELOAD_PRELOAD_ENABLE;sConfig.EncoderMode = TIM_ENCODERMODE_TI1;sConfig.IC1Polarity = TIM_ICPOLARITY_FALLING;sConfig.IC1Selection = TIM_ICSELECTION_DIRECTTI;sConfig.IC1Prescaler = TIM_ICPSC_DIV1;sConfig.IC1Filter = 3;sConfig.IC2Polarity = TIM_ICPOLARITY_FALLING;sConfig.IC2Selection = TIM_ICSELECTION_DIRECTTI;sConfig.IC2Prescaler = TIM_ICPSC_DIV1;sConfig.IC2Filter = 3;if (HAL_TIM_Encoder_Init(&htim4, &sConfig) != HAL_OK){Error_Handler();}sMasterConfig.MasterOutputTrigger = TIM_TRGO_RESET;sMasterConfig.MasterSlaveMode = TIM_MASTERSLAVEMODE_DISABLE;if (HAL_TIMEx_MasterConfigSynchronization(&htim4, &sMasterConfig) != HAL_OK){Error_Handler();}/* USER CODE BEGIN TIM4_Init 2 */HAL_TIM_Encoder_Start(&htim4, TIM_CHANNEL_ALL);/* USER CODE END TIM4_Init 2 */}void HAL_TIM_Encoder_MspInit(TIM_HandleTypeDef* tim_encoderHandle)
{GPIO_InitTypeDef GPIO_InitStruct = {0};if(tim_encoderHandle->Instance==TIM4){/* USER CODE BEGIN TIM4_MspInit 0 *//* USER CODE END TIM4_MspInit 0 *//* TIM4 clock enable */__HAL_RCC_TIM4_CLK_ENABLE();__HAL_RCC_GPIOB_CLK_ENABLE();/**TIM4 GPIO ConfigurationPB6     ------> TIM4_CH1PB7     ------> TIM4_CH2*/GPIO_InitStruct.Pin = GPIO_PIN_6|GPIO_PIN_7;GPIO_InitStruct.Mode = GPIO_MODE_AF_PP;GPIO_InitStruct.Pull = GPIO_PULLUP;GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_VERY_HIGH;GPIO_InitStruct.Alternate = GPIO_AF2_TIM4;HAL_GPIO_Init(GPIOB, &GPIO_InitStruct);/* USER CODE BEGIN TIM4_MspInit 1 *//* USER CODE END TIM4_MspInit 1 */}
}//获取编码器变化
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_USART1_UART_Init();/* USER CODE BEGIN 2 */// exit_init();MX_TIM4_Init();/* USER CODE END 2 *//* Infinite loop *//* USER CODE BEGIN WHILE */int32_t Enc_Count_pre =  __HAL_TIM_GET_COUNTER(&htim4);while (1){/* USER CODE END WHILE *//* USER CODE BEGIN 3 */int32_t Enc_Count =  __HAL_TIM_GET_COUNTER(&htim4);if (Enc_Count != Enc_Count_pre) {printf("%d\r\n", Enc_Count);Enc_Count_pre = Enc_Count;}}/* USER CODE END 3 */
}