How tom change generator frequency

tom321 · May 10, 2025, 1:21pm

Hi
How tom change generator frequency using buttons ?

//https://www.i-programmer.info/programming/148-hardware/17804-programming-the-esp32-in-c-pwm-first-example.html?start=4#google_vignette
#include <driver/ledc.h>
int k;

void setup() {
     Serial.begin(115200);
   pinMode(16, INPUT_PULLUP);    //k++
  pinMode(17, INPUT_PULLUP);   //k--

  // Конфигурация таймера
  ledc_timer_config_t timerConfig = {
    .speed_mode = LEDC_LOW_SPEED_MODE,     
    .duty_resolution = LEDC_TIMER_10_BIT,  
    .timer_num = LEDC_TIMER_0,             
    .freq_hz = 10000,              //+++++++++++++++++++++++++++++        
    .clk_cfg = LEDC_AUTO_CLK               
  };
  ledc_timer_config(&timerConfig);

  
  ledc_channel_config_t channelConfig1 = {
    .gpio_num = 18,  
    .speed_mode = LEDC_LOW_SPEED_MODE,
    .channel = LEDC_CHANNEL_0,  
    .timer_sel = LEDC_TIMER_0,  
    .duty = 512,                
    .hpoint = 0                 
  };
  ledc_channel_config(&channelConfig1);

  
  ledc_channel_config_t channelConfig2 = {
    .gpio_num = 19,  
    .speed_mode = LEDC_LOW_SPEED_MODE,
    .channel = LEDC_CHANNEL_1,  
    .timer_sel = LEDC_TIMER_0,  
    .duty = 512,                
    .hpoint = 256               
  };
  ledc_channel_config(&channelConfig2);
}


void loop()
{
  if (digitalRead(16) == LOW)
  {
    k++;
  }
  if (digitalRead(17) == LOW)
  {
    k--;
  }
  Serial.println(k); 
  delay( 100 ); 
}
/*

void changeFreq(float freq) {
  if (digitalRead(16) == LOW) {
    k++;
  }
  if (digitalRead(17) == LOW) {
    k--;
  }
  Serial.println(k);
  delay(100);
}
*/

Paul_KD7HB · May 10, 2025, 1:56pm

Use a global variable instead of the fixed 10000. Change the global variable to what you want and call the function again.

tom321 · May 10, 2025, 2:13pm

I understand what to do but I don't know how.

Paul_KD7HB · May 10, 2025, 3:11pm

Sorry to tell you that you actually need to spend some time learning about programming and about the C language.

tom321 · May 10, 2025, 3:35pm

I did it this way but k doesn't change

//https://www.i-programmer.info/programming/148-hardware/17804-programming-the-esp32-in-c-pwm-first-example.html?start=4#google_vignette
#include <driver/ledc.h>
int k;
//+++++++++++++++++++++++++++++++
void frequencyChange()  //void somefunc()
// your variable here
{
  if (digitalRead(16) == LOW) {
    k++;
  }
  if (digitalRead(17) == LOW) {
    k--;
  }
  //++++++++++++++ // put your setup code here, to run once:+++++++++++++++

  ledc_timer_config_t timerConfig = {
    .speed_mode = LEDC_LOW_SPEED_MODE,
    .duty_resolution = LEDC_TIMER_10_BIT,
    .timer_num = LEDC_TIMER_0,
    .freq_hz = k,              //+++++++++++++++++++++++++++++
    .clk_cfg = LEDC_AUTO_CLK
  };
  ledc_timer_config(&timerConfig);
  Serial.println(k);
  Serial.println("  k1  ");
  //+++++++++++++++++++++++++++++
}
//+++++++++++++++++++++++++++++++++
void setup() {
  Serial.begin(115200);
  pinMode(16, INPUT_PULLUP);    //k++
  pinMode(17, INPUT_PULLUP);   //k--
  /*
    ledc_timer_config_t timerConfig = {
      .speed_mode = LEDC_LOW_SPEED_MODE,
      .duty_resolution = LEDC_TIMER_10_BIT,
      .timer_num = LEDC_TIMER_0,
      .freq_hz = 10000,              //+++++++++++++++++++++++++++++
      .clk_cfg = LEDC_AUTO_CLK
    };
    ledc_timer_config(&timerConfig);
  */

  ledc_channel_config_t channelConfig1 = {
    .gpio_num = 18,
    .speed_mode = LEDC_LOW_SPEED_MODE,
    .channel = LEDC_CHANNEL_0,
    .timer_sel = LEDC_TIMER_0,
    .duty = 512,
    .hpoint = 0
  };
  ledc_channel_config(&channelConfig1);


  ledc_channel_config_t channelConfig2 = {
    .gpio_num = 19,
    .speed_mode = LEDC_LOW_SPEED_MODE,
    .channel = LEDC_CHANNEL_1,
    .timer_sel = LEDC_TIMER_0,
    .duty = 512,
    .hpoint = 256
  };
  ledc_channel_config(&channelConfig2);
}


void loop()
{

  Serial.println(k);
  Serial.println("  k2  ");
  delay( 100 );
}

PaulRB · May 10, 2025, 3:37pm

Tom who? Have you asked him?

Or are you referring to yourself in the 3rd person?

Paul_KD7HB · May 10, 2025, 4:20pm

So, why not actually debug the code by printing the values where you actually change based on pin reading values? Debugging means tracking down the source of the problem, not just displaying a final value.

tom321 · May 10, 2025, 6:12pm

k2 does not change = 0, when pressing the buttons

Paul_KD7HB · May 10, 2025, 6:19pm

Why not actually display what value is being read form the buttons, rather than show what subsequent code is producing? Come on, get to the source of the error!!!!

tom321 · May 10, 2025, 6:21pm

= 0

tom321 · May 10, 2025, 6:29pm

and this are the readings when buttons are inside void loop()

void loop() {
  if (digitalRead(16) == LOW) {
    k++;
  }
  if (digitalRead(17) == LOW) {
    k--;
  }
Serial.print("  k2 =  ");
  Serial.println(k);
  delay(100);
}

Paul_KD7HB · May 10, 2025, 6:36pm

And what would cause that to happen? Time for a schematic showing the wiring of your switches!

tom321 · May 10, 2025, 7:12pm

switches are working, k2 is changing when buttons are inside void loop.

ledsyn · May 10, 2025, 7:41pm

*Shows picture of k2 = 0*

*Now shows picture of k2 changing*

It sounds like the setup is identical but obviously it cannot be. What did you change?

camsysca · May 10, 2025, 8:07pm

Now that you have a variable that changes, what do you think can be done with it?

tom321 · May 10, 2025, 11:06pm

Variable they should change when they are in

void frequencyChange()

loop, not in

void loop()

camsysca · May 10, 2025, 11:14pm

That function would need to be called in order to execute
when the variable changes, it would seem that there would be a need to reconfigure the timer

Perhaps that could help?

ledsyn · May 11, 2025, 5:22am

If post #16 was directed at me, you need to use Reply.

Just as @camsysca answered you

is never called. WYSIWYG.

tom321 · May 11, 2025, 11:05am

Working code = frequency changes

//https://www.i-programmer.info/programming/148-hardware/17804-programming-the-esp32-in-c-pwm-first-example.html?start=4#google_vignette
#include <driver/ledc.h>
int k;
//const int btn_inc = 16;
//const int btn_dec = 17;
const int maxFreq = 2000;
const int minFreq = 1000;
//unsigned long tim_btn_inc, tim_btn_dec;
//+++++++++++++++++++++++++++++++
// variables will change:
int freq = maxFreq;
int interval = 1; // variables will change:
/*
  //++++++++++++
  void frequencyChange()  //void somefunc()
  // your variable here
  {
  pinMode(16, INPUT_PULLUP);    //k++
  pinMode(17, INPUT_PULLUP);   //k--
  int k;
  if (digitalRead(16) == LOW) {
    k++;
  }
  if (digitalRead(17) == LOW) {
    k--;
  }
  //++++++++++++++ // put your setup code here, to run once:+++++++++++++++

  ledc_timer_config_t timerConfig = {
    .speed_mode = LEDC_LOW_SPEED_MODE,
    .duty_resolution = LEDC_TIMER_10_BIT,
    .timer_num = LEDC_TIMER_0,
    .freq_hz = k,              //+++++++++++++++++++++++++++++
    .clk_cfg = LEDC_AUTO_CLK
  };
  ledc_timer_config(&timerConfig);
  Serial.print("  k1 =  ");
  Serial.println(k);
  //+++++++++++++++++++++++++++++
  }
  //+++++++++++++++++++++++++++++++++
*/
void setup() {
  Serial.begin(115200);
  pinMode(32, INPUT_PULLUP);    //k++
  pinMode(33, INPUT_PULLUP);   //k--
  /*
    ledc_timer_config_t timerConfig = {
      .speed_mode = LEDC_LOW_SPEED_MODE,
      .duty_resolution = LEDC_TIMER_10_BIT,
      .timer_num = LEDC_TIMER_0,
      .freq_hz = 10000,              //+++++++++++++++++++++++++++++
      .clk_cfg = LEDC_AUTO_CLK
    };
    ledc_timer_config(&timerConfig);
  */

  ledc_channel_config_t channelConfig1 = {
    .gpio_num = 12,
    .speed_mode = LEDC_LOW_SPEED_MODE,
    .channel = LEDC_CHANNEL_0,
    .timer_sel = LEDC_TIMER_0,
    .duty = 512,
    .hpoint = 0
  };
  ledc_channel_config(&channelConfig1);


  ledc_channel_config_t channelConfig2 = {
    .gpio_num = 27,
    .speed_mode = LEDC_LOW_SPEED_MODE,
    .channel = LEDC_CHANNEL_1,
    .timer_sel = LEDC_TIMER_0,
    .duty = 512,
    .hpoint = 256
  };
  ledc_channel_config(&channelConfig2);
}


void loop()
{
 
  if (digitalRead(32) == LOW) {
    k++;
    if (k >18000) k = 18000;
    // Serial.println(k); //for debugging purposes
  }
  if (digitalRead(33) == LOW) {
    k--;
    if (k < 5000) k = 5000;
    //Serial.println(k); //for debugging purposes
  }
  
  ledc_timer_config_t timerConfig = {
    .speed_mode = LEDC_LOW_SPEED_MODE,
    .duty_resolution = LEDC_TIMER_10_BIT,
    .timer_num = LEDC_TIMER_0,
    .freq_hz = k,              //+++++++++++++++++++++++++++++
    .clk_cfg = LEDC_AUTO_CLK
  };
  ledc_timer_config(&timerConfig);

  //+++++++++++++++++++++++++++++++
  Serial.print("  k3 =  ");
  Serial.println(k);
  delay( 2 );
}

tom321 · May 11, 2025, 11:08am

When I create separate loop for frequency changing code is not working = no output signal.

//https://www.i-programmer.info/programming/148-hardware/17804-programming-the-esp32-in-c-pwm-first-example.html?start=4#google_vignette
#include <driver/ledc.h>
int k;
//const int btn_inc = 16;
//const int btn_dec = 17;
const int maxFreq = 2000;
const int minFreq = 1000;
//unsigned long tim_btn_inc, tim_btn_dec;
//+++++++++++++++++++++++++++++++
// variables will change:
int freq = maxFreq;
int interval = 1; // variables will change:
/*
  //++++++++++++
  void frequencyChange()  //void somefunc()
  // your variable here
  {
  pinMode(16, INPUT_PULLUP);    //k++
  pinMode(17, INPUT_PULLUP);   //k--
  int k;
  if (digitalRead(16) == LOW) {
    k++;
  }
  if (digitalRead(17) == LOW) {
    k--;
  }
  //++++++++++++++ // put your setup code here, to run once:+++++++++++++++

  ledc_timer_config_t timerConfig = {
    .speed_mode = LEDC_LOW_SPEED_MODE,
    .duty_resolution = LEDC_TIMER_10_BIT,
    .timer_num = LEDC_TIMER_0,
    .freq_hz = k,              //+++++++++++++++++++++++++++++
    .clk_cfg = LEDC_AUTO_CLK
  };
  ledc_timer_config(&timerConfig);
  Serial.print("  k1 =  ");
  Serial.println(k);
  //+++++++++++++++++++++++++++++
  }
  //+++++++++++++++++++++++++++++++++
*/
void setup() {
  Serial.begin(115200);
  pinMode(32, INPUT_PULLUP);    //k++
  pinMode(33, INPUT_PULLUP);   //k--
  /*
    ledc_timer_config_t timerConfig = {
      .speed_mode = LEDC_LOW_SPEED_MODE,
      .duty_resolution = LEDC_TIMER_10_BIT,
      .timer_num = LEDC_TIMER_0,
      .freq_hz = 10000,              //+++++++++++++++++++++++++++++
      .clk_cfg = LEDC_AUTO_CLK
    };
    ledc_timer_config(&timerConfig);
  */

  ledc_channel_config_t channelConfig1 = {
    .gpio_num = 12,
    .speed_mode = LEDC_LOW_SPEED_MODE,
    .channel = LEDC_CHANNEL_0,
    .timer_sel = LEDC_TIMER_0,
    .duty = 512,
    .hpoint = 0
  };
  ledc_channel_config(&channelConfig1);


  ledc_channel_config_t channelConfig2 = {
    .gpio_num = 27,
    .speed_mode = LEDC_LOW_SPEED_MODE,
    .channel = LEDC_CHANNEL_1,
    .timer_sel = LEDC_TIMER_0,
    .duty = 512,
    .hpoint = 256
  };
  ledc_channel_config(&channelConfig2);
}


void loop()
{
}

//++++++++++++
void frequencyChange()  //void somefunc()
// your variable here
{
  if (digitalRead(32) == LOW) {
    k++;
    if (k > 18000) k = 18000;
    // Serial.println(k); //for debugging purposes
  }
  if (digitalRead(33) == LOW) {
    k--;
    if (k < 5000) k = 5000;
    //Serial.println(k); //for debugging purposes
  }

  ledc_timer_config_t timerConfig = {
    .speed_mode = LEDC_LOW_SPEED_MODE,
    .duty_resolution = LEDC_TIMER_10_BIT,
    .timer_num = LEDC_TIMER_0,
    .freq_hz = k,              //+++++++++++++++++++++++++++++
    .clk_cfg = LEDC_AUTO_CLK
  };
  ledc_timer_config(&timerConfig);

  //+++++++++++++++++++++++++++++++
  Serial.print("  k3 =  ");
  Serial.println(k);
  delay( 2 );
}

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