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static void cam_i2s_init()
{
  // Enable and configure I2S peripheral
  periph_module_enable(PERIPH_I2S0_MODULE);
  // Toggle some reset bits in LC_CONF register
  // Toggle some reset bits in CONF register
  i2s_conf_reset();
  // Enable slave mode (sampling clock is external)
  //I2S0.conf.rx_slave_mod = 1;
  I2S0.conf.rx_slave_mod = 0;
  // Enable parallel mode
  I2S0.conf2.lcd_en = 1;
  // Use HSYNC/VSYNC/HREF to control sampling
  I2S0.conf2.camera_en = 1;
  // Configure clock divider
  I2S0.clkm_conf.val = 0;
  I2S0.clkm_conf.clka_en = 0;
  I2S0.clkm_conf.clkm_div_a = 63;
  I2S0.clkm_conf.clkm_div_b = 63;
  I2S0.clkm_conf.clkm_div_num = 80000000L/2000000L;
  // FIFO will sink data to DMA
  I2S0.fifo_conf.dscr_en = 1;
  // FIFO configuration
  I2S0.fifo_conf.rx_fifo_mod = SM_0A0B_0C0D;			//16-bit single channel
  I2S0.fifo_conf.rx_fifo_mod_force_en = 1;
  I2S0.conf_chan.rx_chan_mod = 1;			//only capture Left channel data
  // Clear flags which are used in I2S serial mode
  I2S0.sample_rate_conf.rx_bits_mod = 0;
  I2S0.conf.rx_right_first = 0;				//not skip first sample
  I2S0.conf.rx_msb_right = 0;				//LSB byte received first
  I2S0.conf.rx_msb_shift = 0;				//use MSB Alignment Standard
  I2S0.conf.rx_mono = 0;					//disable mono mode in PCM standard mode
  I2S0.conf.rx_short_sync = 0;				//disable receiver in PCM standard mode
  I2S0.timing.val = 0;

  // Allocate I2S interrupt, keep it disabled
  esp_intr_alloc(ETS_I2S0_INTR_SOURCE,
		  	  	  ESP_INTR_FLAG_INTRDISABLED | ESP_INTR_FLAG_LEVEL1 | ESP_INTR_FLAG_IRAM,
			  &i2s_isr, NULL, &CameraInfo.i2s_intr_handle);

}

Code: Select all

static void gpio_setup_out(int gpio, int sig, int inv) {
    if (gpio == -1) return;
    PIN_FUNC_SELECT(GPIO_PIN_MUX_REG[gpio], PIN_FUNC_GPIO);
    gpio_set_direction(gpio, GPIO_MODE_DEF_OUTPUT);
    gpio_matrix_out(gpio, sig, inv, false);
	}
static void cam_gpio_init()
{
  gpio_num_t pins[] = {
  			CAM_DATA7_IO, CAM_DATA6_IO, CAM_DATA5_IO,
  			CAM_DATA4_IO, CAM_DATA3_IO,	CAM_DATA2_IO,
  			CAM_DATA1_IO, CAM_DATA0_IO, CAM_VSYNC_IO,
  };

    gpio_config_t gpio_conf = {
            .mode = GPIO_MODE_INPUT,
            .pull_up_en = GPIO_PULLUP_ENABLE,
            .pull_down_en = GPIO_PULLDOWN_DISABLE,
            .intr_type = GPIO_INTR_DISABLE
    };
    for (int i = 0; i < sizeof(pins) / sizeof(gpio_num_t); ++i) {
        if (rtc_gpio_is_valid_gpio(pins[i])) {
            rtc_gpio_deinit(pins[i]);
        }
        gpio_conf.pin_bit_mask = 1LL << pins[i];
        gpio_config(&gpio_conf);
    }

    gpio_conf.pin_bit_mask = 1LL << 4;
    gpio_conf.mode = GPIO_MODE_OUTPUT;
    gpio_config(&gpio_conf);
    
    // Route input GPIOs to I2S peripheral using GPIO matrix
    gpio_matrix_in(CAM_DATA0_IO, I2S0I_DATA_IN0_IDX, false);
    gpio_matrix_in(CAM_DATA1_IO, I2S0I_DATA_IN1_IDX, false);
    gpio_matrix_in(CAM_DATA2_IO, I2S0I_DATA_IN2_IDX, false);
    gpio_matrix_in(CAM_DATA3_IO, I2S0I_DATA_IN3_IDX, false);
    gpio_matrix_in(CAM_DATA4_IO, I2S0I_DATA_IN4_IDX, false);
    gpio_matrix_in(CAM_DATA5_IO, I2S0I_DATA_IN5_IDX, false);
    gpio_matrix_in(CAM_DATA6_IO, I2S0I_DATA_IN6_IDX, false);
    gpio_matrix_in(CAM_DATA7_IO, I2S0I_DATA_IN7_IDX, false);
    gpio_matrix_in(CAM_VSYNC_IO, I2S0I_V_SYNC_IDX, true);		
    gpio_matrix_in(0x38, I2S0I_H_SYNC_IDX, false);
    gpio_matrix_in(0x38, I2S0I_H_ENABLE_IDX, false);
    gpio_setup_out(CAM_PCLK_IO, I2S0O_WS_OUT_IDX, false);
}