ESP32 Forum

Posted: **Mon Mar 16, 2020 10:08 pm**

I've got few tests with ledc and i've got strange results.

If we use ledc like this:

Code: [Select all] [Expand/Collapse]

void setup() {
  Serial.begin(115200);
  
  Serial.println(F("Start setup")); 
 
  pinMode(GPIO_NUM_32, OUTPUT);
    pinMode(GPIO_NUM_32, LOW);
    ledcSetup(LEDC_CHANNEL_0, 10000000, 2 );
    ledcAttachPin(GPIO_NUM_32, LEDC_CHANNEL_0);
    ledcWrite(LEDC_CHANNEL_0, 2 );
 
  int time = 0;
  while(1) { Serial.println(time); delay(time++); }
  }

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It means I just want to generate pwm 10mhz on 32 pin. But with this configuration we have got WDT on ~10ms. And some interesting fact that esp32 reset automatically after 10ms and it happens again and again. But some time rst:0x10 (RTCWDT_RTC_RESET),boot:0x33 (SPI_FAST_FLASH_BOOT) happened thas indicate about WDT Reset.

Output example:

Code: [Select all] [Expand/Collapse]

0
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�Start setup
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Start setup
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ets Jun  8 2016 00:22:57
 
rst:0x10 (RTCWDT_RTC_RESET),boot:0x33 (SPI_FAST_FLASH_BOOT)
configsip: 0, SPIWP:0xee
clk_drv:0x00,q_drv:0x00,d_drv:0x00,cs0_drv:0x00,hd_drv:0x00,wp_drv:0x00
mode:DIO, clock div:2
load:0x3fff0018,len:4
load:0xffffffff,len:-1
ets Jun  8 2016 00:22:57

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But if we remove this code and it would be like this:

Code: [Select all] [Expand/Collapse]

void setup() {
  Serial.begin(115200);
  
  Serial.println(F("Start setup")); 
 
  int sec = 0;
  while(1) {
    Serial.println(sec);
    delay(sec++);
  }
  }

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Counter newer stop. And any WDT errors never happens

Code: [Select all] [Expand/Collapse]

Start setup
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187
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1000
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So. What is wrong? Someone please help me

ESP32 Forum

ESP32 Setup ledc affect to wdt time

ESP32 Setup ledc affect to wdt time