24MHz clock issue

[josef2600]

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Issue or Suggestion Description

hi. frankly, i was happy to see you still working on camera. i don't understand why nobody has fixed this one yet, but i have! currently, i am working in here:
https://github.com/s60sc/ESP32-CAM_MJPEG2SD
but i created a pull request there that fixes the clock issue. i have seen your code, but i didn't quite understand why yours doesn't work. i did test it. but if i do it in espressif way, it works. to remind you, i am working with Arduino. but i do not think there is any problem for it to put it to IDF too.
any way, this is the code that can generate 24MHz or 26MHz or any other clocks. i have tested it with oscilloscope. i do know over 20MHz it is not very good, but i tested it with ov5640 and it had no problem. but not just that, i was able to work with it very very more stable. and it did accept 10FPS for framing at full HD. although, it doesn't generate it for streaming. but that is another problem not related.
here is the code i tested for board v 3.1.1 and esp32-s3 and ov5640.
but, since i do not work with your code directly, i have to use you esp_camera_init and then disable the LEDC.

    err = esp_camera_init(&config); // here it only should be 20mhz
    delay(300);// this is base on datasheet. the camera takes under 300ms to be configured. 
    //since the original setup doesnt create over 20MHz clock, we do it forcefully
    // Deinitialize the existing LEDC configuration
    ledc_stop(LEDC_LOW_SPEED_MODE, config.ledc_channel, 0);
    delay(1); // for fun! but really for making sure it stops! and 
    // Configure the LEDC timer
    ledc_timer_config_t ledc_timer =
    {
      .speed_mode = LEDC_LOW_SPEED_MODE,
      .duty_resolution = LEDC_TIMER_1_BIT,
      .timer_num = config.ledc_timer,
      .freq_hz = config.xclk_freq_hz,
      .clk_cfg = LEDC_AUTO_CLK
    };
    if (ledc_timer_config(&ledc_timer) != ESP_OK)
    {
      LOG_ERR("mjpeg2sd.cpp - ledc_timer_config(&ledc_timer) != ESP_OK");
      delay(1000);
    }
    // Configure the LEDC channel
    ledc_channel_config_t ledc_channel =
    {
      .gpio_num = XCLK_GPIO_NUM,
      .speed_mode = LEDC_LOW_SPEED_MODE,
      .channel = config.ledc_channel,
      .intr_type = LEDC_INTR_DISABLE,
      .timer_sel = config.ledc_timer,
      .duty = 1,  // 50% duty cycle for 1-bit resolution
      .hpoint = 0
    };
    
    if (ledc_channel_config(&ledc_channel) != ESP_OK)
    {
      LOG_ERR("mjpeg2sd.cpp - ledc_channel_config(&ledc_channel) != ESP_OK");
      delay(1000);
    }
    delay(300);//fun fun!

datasheet say put a delay(300);. this is base on datasheet. the camera takes under 300ms to be configured for the settings we gave it.
and this is the test:
https://private-user-images.githubusercontent.com/24930536/402267861-c25c15f6-575b-4b68-99e3-1ec4e22dfd42.jpg?jwt=eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.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.aFueJcfoo6bsyfo97npRLJhPdeIWhGN371lJf-EwAKg

and if you are interested, this is my discussion and my board pictures!
s60sc/ESP32-CAM_MJPEG2SD#540 (reply in thread)
please check the code.
by the way, all clocks in high frequency are sin wave. the 20mhz is sin way too, but it is more pure. but the camera can handel it since they all have schmitt trigger input