Control a Motor

Projects Programming
1

Hey Guys

I am on a project for myselft just4fun.

I am using a Nextion display and an ESP 32 board.

My simple project so far. I have an "UP" button where i can control the brightness of a LED.
Till now (imo) it works quiet well.
The brightness of the LED stand symbolic for the power of a motor. In the future i will try to control a motor with the code

Here is the code:

/******************************************

 ****************************************/

//Librarys
#include <Nextion.h>
#include <iostream>
using namespace std;

//Fading LED
int freq = 5000;
int ledChannel = 0;
int resolution = 8;

// LED Pins
int Dosierungs_LED = 25;


//Display
HardwareSerial Serial2(2);


void t0PopCallback(void *ptr);
void b1PopCallback(void *ptr);
void b2PopCallback(void *ptr);

NexText t0      = NexText(2, 5, "t0");
NexButton b1    = NexButton(2, 2, "b1");
NexButton b2    = NexButton(2, 3, "b2");
char buffer[100] = {0};


NexTouch *nex_listen_list[] =
{
  &b1,     //Up
  &b2,     //Down
  &t0,
  NULL
};

void t0PopCallback(void *ptr)
{
  t0.setText("50");
}

void b1PopCallback(void *ptr)
{
  uint16_t len;
  double number2;
  uint16_t number;
  memset(buffer, 0, sizeof(buffer));
  t0.getText(buffer, sizeof(buffer));
  number = atoi(buffer);
  number2 = atof(buffer);

  if ( number >= 1 && number <100)
  {
    number += 1;
    memset(buffer, 0, sizeof(buffer));
    itoa(number, buffer, 10);
    t0.setText(buffer);
    
  }

  else if ( number2 >=0.0 && number2 <=0.98)
  {
    number2 += 0.01;  
    writeFloatToDisplay(t0, number2);
   
  }
  else if (number2 >=0.99 && number2< 1.00)
  {
  t0.setText("1");
  }
  
}

void setup(void)
{
  //Serial COM
  Serial.begin(115200);
  Serial2.begin(9600);

  Serial.println("Monitoring interrupts: ");

  // LED - Pins
  pinMode(Dosierungs_LED, OUTPUT);
  
  nexInit();
  t0.attachPop(t0PopCallback);
  b1.attachPop(b1PopCallback);
  
  //PWM für ESP32
  ledcSetup(ledChannel, freq, resolution);
  ledcAttachPin(25, ledChannel);

}

void loop(void)
{
  nexLoop(nex_listen_list);
  double value = map(pumpLeistung(), 0, 100, 0, 255); 
  ledcWrite(ledChannel, value); 
  delay(100);
}


//----------------------------------------------------------------
//------------------------ FUNCTIONS------------------------------
//----------------------------------------------------------------

float writeFloatToDisplay(NexText target, double value)
{ char buffer[10];
  dtostrf(value, 5, 2, buffer);
  target.setText(buffer);
}

double pumpLeistung()
{
  double value;
  memset(buffer, 0, sizeof(buffer));
  t0.getText(buffer, sizeof(buffer));
  value = atof(buffer); 
  return value;
}

My questions now: 1) Is it necessary to have ledcWrite-function in the loop? I somehow have the feeling it costs me much memorypower of my board. Because from my point of view it now looks every 100ms for a value and sends it to the LED. Is there a more efficiency way?

  1. Problem. When i upload my code to my esp32. the up button works fine. the value of the field "t0" changes and with the UP-button and so the brightness of the LED. BUT. When i unplug my ESP32 from my computer and replug it back. The button does not work and in the field "t0" on my nextion, nothing is there. To solve it. I must reupload the code to my ESP32. Someone has an idea?

Thank u very much

Best regards

2
  1. Is it necessary to have ledcWrite-function in the loop?

You can't have a function in a loop. You can have a call to a function in a loop.

Which loop are you talking about?

To solve it. I must reupload the code to my ESP32. Someone has an idea?

It sounds like your power supply for the ESP32 is inadequate. How ARE you powering it when the USB cable is not connected?

3

Hello PaulS

I am talking about the "main-loop"

void loop(void)
{
  nexLoop(nex_listen_list);
  double value = map(pumpLeistung(), 0, 100, 0, 255); 
  ledcWrite(ledChannel, value); 
  delay(100);
}

There i call the function map() and ledcWrite(). I somehow have the feeling its not very performy.

About the power. Till now im powering my ESP only with the USB-cable. Until now, i never had the problem. So i am a little bit confused now.

Thanks

Best regards

4 
  double value = map(pumpLeistung(), 0, 100, 0, 255);

All 5 arguments to the map function are integral values. The output is an integral value. Storing that in a double is pointless.

I somehow have the feeling its not very performy.

I don't understand you when you get all technical.

You could improve the performance of your code by only calling ledcWrite() when there is a new value to write. This means, of course, of keeping track of what value you have written to the device.