Esp32 mcpwm issues

[sacd]

Hi all,

I am need to generate complementary PWM using MCPWM. The duty cycle needs to be of typically 5us and time period 10us. While search through forum, I found a code for PWM (not complementary). I am trying to change frequency and duty. However the code seems to work sometimes and some times it doesn't. I removed a syn() line form original code posted in ( ESP32 mcPWM) . As I am new to using MCPWM can somebody suggest what needs to be done.

#include "driver/mcpwm.h"
//MCPWM TRY 2

// REF:https://forum.arduino.cc/t/esp32-mcpwm/608899


                       
#define MOSFET 22          //pin to trigger the MOSFET (Output) pin22

void setup() {
  // put your setup code here, to run once:
  mcpwm_gpio_init(MCPWM_UNIT_0, MCPWM0A, MOSFET);


  mcpwm_pin_config_t pin_config; 
   // pin_config.mcpwm_sync0_in_num  = GPIO_SYNC0_IN;
      
  mcpwm_config_t pwm_config;
    pwm_config.frequency = 100000;    //frequency = 110Hz
    pwm_config.cmpr_a = 50;       //duty cycle of PWMxA = 60.0%
    pwm_config.counter_mode = MCPWM_UP_COUNTER;
    pwm_config.duty_mode = MCPWM_DUTY_MODE_0;
    mcpwm_set_pin(MCPWM_UNIT_0, &pin_config);



  mcpwm_init(MCPWM_UNIT_0, MCPWM_TIMER_0, &pwm_config);   //Configure PWM0A & PWM0B with above settings
  mcpwm_set_duty_type(MCPWM_UNIT_0, MCPWM_TIMER_0, MCPWM_OPR_A, MCPWM_DUTY_MODE_0);
  mcpwm_start(MCPWM_UNIT_0, MCPWM_TIMER_0);
  //mcpwm_sync_enable(MCPWM_UNIT_0, MCPWM_TIMER_0, MCPWM_SELECT_SYNC0, 0);
  mcpwm_set_duty(MCPWM_UNIT_0, MCPWM_TIMER_0, MCPWM_OPR_A,50);
}

void loop() {

}

[ruilviana]

@sacd

mcpwm

Here you have more information about MCPWM.

"MCPWM - ESP32 - — ESP-IDF Programming Guide v4.3 documentation

"https://www.instructables.com/Electric-Turbine-With-ESP32/

[sacd]

Thanks Ruilviana,

Based on the example reference. I was able to modify the code and get basic PWM.

The issue was due to
mcpwm_start(MCPWM_UNIT_0, MCPWM_TIMER_0);

and

additional lines
mcpwm_set_pin(MCPWM_UNIT_0, &pin_config);
mcpwm_pin_config_t pin_config;

When these lines were removed. The PWM is being generated.

WIll check now for comlementary generation.