ESP32 Forum

Posted: **Fri Mar 13, 2020 8:19 am**

Using ADC+I2S alone works:
- Test: Simply Connect the ADC-Input to 3V3, and we got 0X0FFF in the Buffer as expected --> OK

BUG:
Simply adding the Line
"dac_output_enable(DAC_CHANNEL_1)"
somewere! in the Project - even after the test1,
then the test reads only 0X0000 from the ADC-via spi

seems to be a conflict in the Startup of the library
or some missing initialisation?

Code: [Select all] [Expand/Collapse]

 
#include <stdint.h>
#include "freertos/FreeRTOS.h"
#include "freertos/task.h"
#include "esp_log.h"
 
// DAC-Cosinus
#include "soc/rtc_io_reg.h" //Used by DAC-Sin
#include "soc/rtc_cntl_reg.h"
#include "soc/rtc.h"
 
#include "driver/i2s.h"
#include "driver/adc.h"
#include "driver/dac.h"
#include "esp_adc_cal.h"
#include <soc/syscon_reg.h>
 
#define TAG "MyTag"
#define EXAMPLE_I2S_ADC_CHANNEL     ADC1_CHANNEL_0 /*!< ADC1 channel 0 is GPIO36 (ESP32), GPIO1 (ESP32-S2) */
//Externaly  Connect GPIO36 to 3v3
 
void MyTask(void* arg)
{
    i2s_config_t i2s_config = {
//                  .mode = I2S_MODE_MASTER | I2S_MODE_RX | I2S_MODE_TX | I2S_MODE_DAC_BUILT_IN | I2S_MODE_ADC_BUILT_IN,
                .mode = I2S_MODE_MASTER | I2S_MODE_RX                                       | I2S_MODE_ADC_BUILT_IN,
       .sample_rate =  16000,
       .bits_per_sample = I2S_BITS_PER_SAMPLE_16BIT,
       .communication_format = I2S_COMM_FORMAT_I2S,
       .channel_format = I2S_CHANNEL_FMT_RIGHT_LEFT,
       .intr_alloc_flags = 1,
       .dma_buf_count = 2,
       .dma_buf_len = 1024,
       .use_apll = 0,
    };
    adc1_config_channel_atten(EXAMPLE_I2S_ADC_CHANNEL, ADC_ATTEN_11db);
    adc1_config_width(ADC_WIDTH_BIT_12);
    i2s_driver_install(I2S_NUM_0, &i2s_config, 0, NULL);
    i2s_set_adc_mode(ADC_UNIT_1, EXAMPLE_I2S_ADC_CHANNEL);
    i2s_adc_enable(I2S_NUM_0);
 
    const static size_t i2s_read_len = 1024;
    size_t    bytes_read;
    char*    i2s_read_buff    = (char*) calloc(i2s_read_len, sizeof(char));
 
    ESP_LOGI(TAG, "Test1: expect dump of 0X0FFF");
    i2s_read(EXAMPLE_I2S_NUM, (void*) i2s_read_buff, i2s_read_len, &bytes_read, portMAX_DELAY);
    if(bytes_read>0){
       ESP_LOG_BUFFER_HEXDUMP(TAG, i2s_read_buff, bytes_read, ESP_LOG_INFO );
    }
    vTaskDelay(2/portTICK_PERIOD_MS);
 
 
    dac_cosine_enable(DAC_CHANNEL_1);
   //********************* BUG BUG BUG BUG BUG ******************************************
   // Simply enabeling "dac_output_enable" in Project --> BOTH!!!  Test1 and Test2 will Fail( read only 0X0000)
#if 1
    ESP_LOGI(TAG, "dac_output_enable");
    dac_output_enable(DAC_CHANNEL_1);// GPIO25
#endif
 
 
    ESP_LOGI(TAG, "\nTest2:");
    i2s_read(EXAMPLE_I2S_NUM, (void*) i2s_read_buff, i2s_read_len, &bytes_read, portMAX_DELAY);
    if(bytes_read>0){
       ESP_LOG_BUFFER_HEXDUMP(TAG, i2s_read_buff, bytes_read, ESP_LOG_INFO );
    }
 
    while(1){
        vTaskDelay(2000/portTICK_PERIOD_MS);
    }//while
}
 
 
void  ADC_SPI_DAC_Init(){
     xTaskCreate(MyTask, "MyTask", 1024*3, NULL, 10, NULL);
}
 

ESP32 Forum

ADC+I2S(DMA) conficts with "dac_output_enable": ADC reads 0x00 Values

ADC+I2S(DMA) conficts with "dac_output_enable": ADC reads 0x00 Values