kopia lustrzana https://github.com/donnersm/FFT_ESP32_Analyzer
80 wiersze
4.5 KiB
C
80 wiersze
4.5 KiB
C
/********************************************************************************************************************************************************
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* *
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* Project: FFT Spectrum Analyzer *
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* Target Platform: ESP32 *
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* *
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* Version: 1.0 *
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* Hardware setup: See github *
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* Spectrum analyses done with analog chips MSGEQ7 *
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* *
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* Mark Donners *
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* The Electronic Engineer *
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* Website: www.theelectronicengineer.nl *
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* facebook: https://www.facebook.com/TheelectronicEngineer *
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* youtube: https://www.youtube.com/channel/UCm5wy-2RoXGjG2F9wpDFF3w *
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* github: https://github.com/donnersm *
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* *
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********************************************************************************************************************************************************/
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#pragma once
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#include <driver/i2s.h>
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#include <driver/adc.h>
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//Settings
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const int samplingFrequency = 44100;
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const int SAMPLEBLOCK = 1024;
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const i2s_port_t I2S_PORT = I2S_NUM_0;
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void setupI2S() {
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Serial.println("Configuring I2S...");
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esp_err_t err;
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// The I2S config as per the example
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const i2s_config_t i2s_config = {
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.mode = (i2s_mode_t)(I2S_MODE_MASTER | I2S_MODE_RX | I2S_MODE_ADC_BUILT_IN),
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.sample_rate = samplingFrequency,
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.bits_per_sample = I2S_BITS_PER_SAMPLE_16BIT, // could only get it to work with 32bits
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.channel_format = I2S_CHANNEL_FMT_ONLY_LEFT, // although the SEL config should be left, it seems to transmit on right
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.communication_format = I2S_COMM_FORMAT_I2S_MSB,
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.intr_alloc_flags = ESP_INTR_FLAG_LEVEL1, // Interrupt level 1
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.dma_buf_count = 2, // number of buffers
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.dma_buf_len = SAMPLEBLOCK, // samples per buffer
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.use_apll = false,
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.tx_desc_auto_clear = false,
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.fixed_mclk = 0
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};
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// Configuring the I2S driver and pins.
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// This function must be called before any I2S driver read/write operations.
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err = adc_gpio_init(ADC_UNIT_1, ADC_CHANNEL_0); //step 1
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if (err != ESP_OK) {
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Serial.printf("Failed setting up adc channel: %d\n", err);
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while (true);
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}
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err = adc_gpio_init(ADC_UNIT_1, ADC_CHANNEL_3); //step 1
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if (err != ESP_OK) {
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Serial.printf("Failed setting up adc channel: %d\n", err);
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while (true);
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}
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err = i2s_driver_install(I2S_NUM_0, &i2s_config, 0, NULL); //step 2
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if (err != ESP_OK) {
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Serial.printf("Failed installing driver: %d\n", err);
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while (true);
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}
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err = i2s_set_adc_mode(ADC_UNIT_1, ADC1_CHANNEL_0);
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if (err != ESP_OK) {
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Serial.printf("Failed setting up adc mode: %d\n", err);
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while (true);
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}
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Serial.println("I2S driver installed.");
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}
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