C++ Blynk (Legacy) - Code Examples for Basic Tasks

Gunner · October 30, 2018, 10:32am

#23 - Basic Stepper Motor Control

Who says Blynk can’t control Stepper motors… well, OK, I have said it may require fancy non-blocking timing… so here it is (disclaimer, not all that fancy after all )

Yes, it is using the old and decrepit Stepper.h library… only because I was too lazy to learn simple accelStepper commands at this moment

I am also controlling a 4.29v 1.8deg NEMA 17 stepper with an equally old L298D motor controller… Hey, I works with what I gots

UPDATE - Chose the commented out commands for ESP8266 (default) or ESP32, both with OTA (no I haven’t mastered #ifndef yet )

Uses a Slider Widget for speed - Slider V0 set with 0-100 and Send On Release ON (But if you really want it OFF, preferably at around 300-500ms, so you don’t flood the connection unnecessarily).

And a Button Widget for direction - Button V1 set as Switch with 0-1

#define BLYNK_PRINT Serial // This prints to Serial Monitor
//#define BLYNK_DEBUG  // Optional, this enables more detailed prints

////  Pick one Blynk Device Library group or other
////----------
// #include <WiFi.h>  // for ESP32
// #include <WiFiClient.h>  // for ESP32
// #include <BlynkSimpleEsp32.h>  // for ESP32
////----------
#include <ESP8266WiFi.h>  // for ESP8266
#include <BlynkSimpleEsp8266.h>  // for ESP8266
////----------

////  Pick one OTA Library or other
////----------
// #include <ESPmDNS.h>  // For OTA w/ ESP32
////----------
#include <ESP8266mDNS.h>  // For OTA w/ ESP8266
////----------

#include <WiFiUdp.h>  // For OTA
#include <ArduinoOTA.h>  // For OTA

char auth[] = "xxxxxxxxxx";
char ssid[] = "xxxxx";
char pass[] = "xxxxx";
//char server[] = "xxx.xxx.xxx.xxx";  // IP for your Local Server
char server[] = "blynk-cloud.com";  // URL for Blynk Cloud Server
int port = 8080;

BlynkTimer timer;

#include <Stepper.h>
const int stepsPerRevolution = 200;  // change this to fit the number of steps per revolution for your motor

// ESP8266 use GPIO pin designation, not silk-screened labeling
Stepper myStepper(stepsPerRevolution, 5, 4, 0, 2); // ESP8266 - initialize the stepper library for IN1, IN2, IN3, IN4

// ESP32 GPIO/Silk-screened pin designation
//Stepper myStepper(stepsPerRevolution, 15,2,0,4); // ESP32 - initialize the stepper library for IN1, IN2, IN3, IN4

int motorSpeed;
int motorDirection;



void setup() {
  Serial.begin(9600);

  timer.setInterval(10, stepperControl);  // This here is all the fancy timing part... it just updates the stepper control every 5ms

  WiFi.begin(ssid, pass);
  Blynk.config(auth, server, port);
  Blynk.connect();

  ArduinoOTA.setHostname("ESP Blynk Stepper");  // For OTA - Use your own device identifying name
  ArduinoOTA.begin();  // For OTA
}


void loop() {
  Blynk.run();
  timer.run();
  ArduinoOTA.handle();  // For OTA
}



BLYNK_CONNECTED() {
  Blynk.syncVirtual(V0, V1);
}

BLYNK_WRITE(V0) {  // Motor Speed - Slider set with 0-100 and Send On Relese OFF
  motorSpeed = param.asInt();
  myStepper.setSpeed(motorSpeed);
}

BLYNK_WRITE(V1) {  // Motor Direction - Button set as Switch with 0-1
  motorDirection = param.asInt();
}



void stepperControl() {
  if (motorSpeed > 0) {
    if (motorDirection == 0) {  // Rotate Clockwise
      myStepper.step(stepsPerRevolution / 100);
    } else {  // Rotate CounterClockwise
      myStepper.step(-stepsPerRevolution / 100);
    }
  }
}