ESP32(ESP-IDF)+CNC Shield+A4988控制步进电机

陈拓 2023/04/15-2023/04/15

1. 简介

在《Arduino Uno开发板+电机驱动扩展版CNC Shield V3.0硬件说明》

https://blog.csdn.net/chentuo2000/article/details/129851439?spm=1001.2014.3001.5502

一文中我们介绍了CNC Shield V3.0的引脚功能以及和Arduino Uno开发板引脚位置的对应关系。

在此基础上，在《D1 R32 – ESP32+Arduino CNC Shield控制步进电机》

https://blog.csdn.net/chentuo2000/article/details/129986246?spm=1001.2014.3001.5502

一文中我们讲述了用ESP32+Arduino CNC Shield通过A4988步进电机驱动模块控制NEMA17步进电机。所给出的例子是Arduino开发环境下的。

本文我们介绍一个ESP-IDF开发环境下的例子。

• ESP32开发板 + Arduino CNC Shield V3.00 + A4988组合

 

2. 软件开发环境

参考《Ubuntu构建ESP32 ESP-IDF开发环境(简约版)》

https://blog.csdn.net/chentuo2000/article/details/128034585?spm=1001.2014.3001.5502

3. 步进电机控制例程

代码来自[https://github.com/arnosolo/esp32-stepmotor]

4. 构建项目

4.1 项目结构

• 进入项目目录

cd ~/esp442/cnc_shield_idf

• 项目结构

 

4.2 配置文件和代码文件

• 顶层CMakeLists.txt

cmake_minimum_required(VERSION 3.5)

include($ENV{IDF_PATH}/tools/cmake/project.cmake)
project(cnc_shield_idf)

• main目录下的CMakeLists.txt

idf_component_register(SRCS "main.cpp" "stepper.cpp"
                    INCLUDE_DIRS "include")

•  stepper.h、stepper.cpp、main.cpp见附录。

4.3 构建项目

• 刷新esp-idf环境

get_idf

• 设定目标芯片

idf.py set-target esp32

• 配置项目

idf.py menuconfig

1) 将闪存设置为4MB

 

保存，退出。

• 编译项目

idf.py build

• 烧写项目

查看ESP32开发板连接电脑的串口：

ls -l /dev/ttyUSB*

修改串口权限：

sudo chmod 777 /dev/ttyUSB0

烧写：

idf.py -p /dev/ttyUSB0 -b 115200 flash

5. 测试

插上CNC Shield扩展板，接上USB线用于给ESP32供电，接上12V电源给电机供电。

• 打开串口监视器

idf.py monitor -p /dev/ttyUSB0

 电机顺时针转动几圈。

附：代码

• stepper.h

#include 
#include 
#include "freertos/FreeRTOS.h"
#include "freertos/task.h"
#include "freertos/queue.h"
#include "freertos/timers.h"
#include "driver/gpio.h"
#include "esp_intr_alloc.h"
#include "esp_log.h"
#include "driver/mcpwm.h"
// #include "soc/mcpwm_periph.h"
#include "soc/mcpwm_reg.h"
#include "soc/mcpwm_struct.h"
#include "driver/pcnt.h"

#define STEPMOTOR_NUM 6
#define PCNT_H_LIM_VAL 1000

typedef struct
{
    int unit;        // the PCNT unit that originated an interrupt
    uint32_t status; // information on the event type that caused the interrupt
} pcnt_evt_t;

typedef struct
{
  mcpwm_unit_t mcpwm_unit;
  mcpwm_timer_t mcpwm_timer;
  mcpwm_io_signals_t mcpwm_io_signals;
  pcnt_unit_t pcnt_unit;
  // pcnt_channel_t pcnt_channel;
} stepmotor_config_t;

static stepmotor_config_t motor_config[STEPMOTOR_NUM] = {
    {.mcpwm_unit = MCPWM_UNIT_0,
    .mcpwm_timer = MCPWM_TIMER_0,
    .mcpwm_io_signals = MCPWM0A,
    .pcnt_unit = PCNT_UNIT_0
    },
    {.mcpwm_unit = MCPWM_UNIT_0,
    .mcpwm_timer = MCPWM_TIMER_1,
    .mcpwm_io_signals = MCPWM1A,
    .pcnt_unit = PCNT_UNIT_1
    },
    {.mcpwm_unit = MCPWM_UNIT_0,
    .mcpwm_timer = MCPWM_TIMER_2,
    .mcpwm_io_signals = MCPWM2A,
    .pcnt_unit = PCNT_UNIT_2
    },
    {.mcpwm_unit = MCPWM_UNIT_1,
    .mcpwm_timer = MCPWM_TIMER_0,
    .mcpwm_io_signals = MCPWM0A,
    .pcnt_unit = PCNT_UNIT_3
    },
    {.mcpwm_unit = MCPWM_UNIT_1,
    .mcpwm_timer = MCPWM_TIMER_1,
    .mcpwm_io_signals = MCPWM1A,
    .pcnt_unit = PCNT_UNIT_4
    },
    {.mcpwm_unit = MCPWM_UNIT_1,
    .mcpwm_timer = MCPWM_TIMER_2,
    .mcpwm_io_signals = MCPWM2A,
    .pcnt_unit = PCNT_UNIT_5
    },
};

class Stepmotor
{
private:
public:
  int id;
  int dirPin;
  int stepPin;
  int speed;
  int step;
  bool isReady;

  static xQueueHandle pcnt_evt_queue;
  static bool status[6];

  Stepmotor(int idInput, int dirPinInput, int stepPinInput);
  void init();
  void move(int stepInput, int speedInput);
  void stop();

};

• stepper.cpp

#include 
#include 
#include "freertos/FreeRTOS.h"
#include "freertos/task.h"
#include "freertos/queue.h"
#include "freertos/timers.h"
#include "driver/gpio.h"
#include "esp_intr_alloc.h"
#include "esp_log.h"
#include "driver/mcpwm.h"
// #include "soc/mcpwm_periph.h"
#include "soc/mcpwm_reg.h"
#include "soc/mcpwm_struct.h"
#include "driver/pcnt.h"
#include "stepper.h"

xQueueHandle Stepmotor::pcnt_evt_queue = xQueueCreate(12, sizeof(pcnt_evt_t));
bool Stepmotor::status[6] = {false, false, false, false, false, false};

static void IRAM_ATTR pcnt_example_intr_handler(void *arg)
{
  int pcnt_unit = (int)arg;
  pcnt_evt_t evt;
  evt.unit = pcnt_unit;

  pcnt_get_event_status((pcnt_unit_t)pcnt_unit, &evt.status);
  // xQueueSendFromISR(Stepmotor::pcnt_evt_queue, &evt, NULL); // defult way

  // int id = pcnt_unit;
  Stepmotor::status[pcnt_unit] = true;
  mcpwm_stop(motor_config[pcnt_unit].mcpwm_unit, motor_config[pcnt_unit].mcpwm_timer);
}

Stepmotor::Stepmotor(int idInput, int dirPinInput, int stepPinInput)
{
  id = idInput;
  dirPin = dirPinInput;
  stepPin = stepPinInput;

  // 1.初始化转动方向引脚
  gpio_config_t io_conf = {};
  io_conf.pin_bit_mask = 1ULL << dirPin;
  io_conf.mode = GPIO_MODE_OUTPUT;
  gpio_config(&io_conf);
  gpio_set_level((gpio_num_t)dirPin, 1);

  // 2.初始化脉冲计数器
  pcnt_unit_t unit = motor_config[id].pcnt_unit;
  pcnt_config_t pcnt_config;
  // Set PCNT input signal and control GPIOs
  pcnt_config.pulse_gpio_num = stepPin,
  pcnt_config.ctrl_gpio_num = PCNT_PIN_NOT_USED,
  pcnt_config.channel = PCNT_CHANNEL_0,
  pcnt_config.unit = unit,
  // What to do on the positive / negative edge of pulse input?
  pcnt_config.pos_mode = PCNT_COUNT_INC, // Count up on the positive edge
  pcnt_config.neg_mode = PCNT_COUNT_DIS, // Keep the counter value on the negative edge
  // What to do when control input is low or high?
  pcnt_config.lctrl_mode = PCNT_MODE_KEEP,
  pcnt_config.hctrl_mode = PCNT_MODE_KEEP, // Keep the primary counter mode if high
  // Set the maximum and minimum limit values to watch
  pcnt_config.counter_h_lim = PCNT_H_LIM_VAL,
  // .counter_l_lim = PCNT_L_LIM_VAL,
  pcnt_unit_config(&pcnt_config);

  /* Configure and enable the input filter */
  pcnt_set_filter_value(unit, 100);
  pcnt_filter_enable(unit);

  pcnt_event_enable(unit, PCNT_EVT_H_LIM);

  /* Initialize PCNT's counter */
  pcnt_counter_pause(unit);
  pcnt_counter_clear(unit);

  /* Install interrupt service and add isr callback handler */
  pcnt_isr_service_install(0);
  pcnt_isr_handler_add(unit, pcnt_example_intr_handler, (void *)unit);

  /* Everything is set up, now go to counting */
  pcnt_counter_resume(unit);

  // 3.生成电机控制脉冲
  // 细分为16,所以一圈需要3200步. 每秒800个脉冲,则电机大概4s转一圈
  ESP_ERROR_CHECK(mcpwm_gpio_init(motor_config[id].mcpwm_unit, motor_config[id].mcpwm_io_signals, stepPin));

  mcpwm_config_t pwm_config;
  pwm_config.frequency = 1000; //frequency = 50Hz
  pwm_config.cmpr_a = 50;      //duty cycle of PWMxA = 50.0%
  pwm_config.counter_mode = MCPWM_UP_COUNTER;
  pwm_config.duty_mode = MCPWM_DUTY_MODE_0;
  ESP_ERROR_CHECK(mcpwm_init(motor_config[id].mcpwm_unit, motor_config[id].mcpwm_timer, &pwm_config));


  // 这么搞一下同一个引脚就既能输出pwm,又能读取脉冲数了...
  gpio_iomux_in(stepPin, PCNT_SIG_CH0_IN0_IDX);

  isReady = true;
  Stepmotor::status[id] = isReady;
  const char *TAG = "motor class";
  ESP_LOGI(TAG, "init complete");
};

/**
 * @brief Ask step motor to move
 *
 * @param stepInput step number, should >= 0. Negative values ​​are converted to positive values
 * @param speedInput speed, step/s
 */
void Stepmotor::move(int stepInput, int speedInput)
{
  isReady = false;
  Stepmotor::status[id] = isReady;
  speed = speedInput;

  if(stepInput < 0) {
    step = -stepInput;
  } else {
    step = stepInput;
  }

  if (speed == 0)
  {
    stop();
  }
  else
  {
    if (speed < 0)
    {
      gpio_set_level((gpio_num_t)dirPin, 0);
      speed = -speedInput;
    }
    else
    {
      gpio_set_level((gpio_num_t)dirPin, 1);
    }

    pcnt_unit_t unit = motor_config[id].pcnt_unit;
    pcnt_set_event_value(unit, PCNT_EVT_H_LIM, (int16_t)step);
    pcnt_event_enable(unit, PCNT_EVT_H_LIM);
    pcnt_counter_pause(unit);
    pcnt_counter_clear(unit);
    pcnt_counter_resume(unit);

    mcpwm_set_frequency(motor_config[id].mcpwm_unit, motor_config[id].mcpwm_timer, speed);
    mcpwm_start(motor_config[id].mcpwm_unit, motor_config[id].mcpwm_timer);
  }
};

void Stepmotor::stop()
{
  // isReady = true;
  // Stepmotor::status[id] = isReady;
  mcpwm_stop(motor_config[id].mcpwm_unit, motor_config[id].mcpwm_timer);
};

• main.cpp

#include 
#include 
#include "freertos/FreeRTOS.h"
#include "freertos/task.h"
#include "freertos/queue.h"
#include "freertos/timers.h"
#include "driver/gpio.h"
#include "esp_intr_alloc.h"
#include "esp_log.h"
#include "stepper.h"

const char *TAG = "Motor Control";

/*********** Tasks ***********/
void clock(void *arg)
{
    const char *TAG = "Clock";
    int cnt = 0;
    while (1)
    {
        ESP_LOGI(TAG, "%d s", cnt);
        cnt++;
        vTaskDelay(1000 / portTICK_RATE_MS);
    }
}

/*********** Main ***********/
extern "C" void app_main(void)
{
    // 1.Create a motor instance
    Stepmotor motorX(0, 16, 26); // id(0~6), dirPin, stepPin

    xTaskCreate(clock, "clock", 2048, NULL, 5, NULL);

    int cnt = 1;
    while (1)
    {
        // 2.Update motor status
        motorX.isReady = Stepmotor::status[motorX.id];

        // 3.Ask the motor move a little
        if (motorX.isReady)
        {
            ESP_LOGI(TAG, "motorX start moving, %d steps at %d step/s", cnt * 500, 500);
            motorX.move(cnt * 500, 500); // stepNum, speed(step/s)
            cnt++;
        }

        if (cnt == 4)
        {
            ESP_LOGI(TAG, "motorX stop");
            motorX.stop();
            cnt++;
        }

        vTaskDelay(10 / portTICK_RATE_MS);
    }
}