kopia lustrzana https://github.com/espressif/esp-idf
114 wiersze
4.9 KiB
C
114 wiersze
4.9 KiB
C
/*
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* SPDX-FileCopyrightText: 2021-2022 Espressif Systems (Shanghai) CO LTD
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*
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* SPDX-License-Identifier: Unlicense OR CC0-1.0
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*/
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#include <stdint.h>
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#include <math.h>
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#include "freertos/FreeRTOS.h"
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#include "freertos/task.h"
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#include "driver/i2s_pdm.h"
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#include "driver/gpio.h"
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#include "esp_check.h"
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#include "sdkconfig.h"
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#include "i2s_pdm_example.h"
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#define EXAMPLE_PDM_TX_CLK_IO GPIO_NUM_4 // I2S PDM TX clock io number
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#define EXAMPLE_PDM_TX_DOUT_IO GPIO_NUM_5 // I2S PDM TX data out io number
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#define EXAMPLE_PDM_TX_FREQ_HZ 44100 // I2S PDM TX frequency
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#define EXAMPLE_WAVE_AMPLITUDE (1000.0) // 1~32767
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#define CONST_PI (3.1416f)
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#define EXAMPLE_SINE_WAVE_LEN(tone) (uint32_t)((EXAMPLE_PDM_TX_FREQ_HZ / (float)tone) + 0.5) // The sample point number per sine wave to generate the tone
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#define EXAMPLE_TONE_LAST_TIME_MS 500
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#define EXAMPLE_BYTE_NUM_EVERY_TONE (EXAMPLE_TONE_LAST_TIME_MS * EXAMPLE_PDM_TX_FREQ_HZ / 1000)
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/* The frequency of tones: do, re, mi, fa, so, la, si, in Hz. */
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static const uint32_t tone[3][7] = {{262, 294, 330, 349, 392, 440, 494}, // bass
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{523, 587, 659, 698, 784, 880, 988}, // alto
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{1046, 1175, 1318, 1397, 1568, 1760, 1976}}; // treble
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/* Numbered musical notation of 'twinkle twinkle little star' */
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static const uint8_t song[28] = {1, 1, 5, 5, 6, 6, 5,
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4, 4, 3, 3, 2, 2, 1,
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5, 5, 4, 4, 3, 3, 2,
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5, 5, 4, 4, 3, 3, 2};
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/* Rhythm of 'twinkle twinkle little star', it's repeated in four sections */
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static const uint8_t rhythm[7] = {1, 1, 1, 1, 1, 1, 2};
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static const char *tone_name[3] = {"bass", "alto", "treble"};
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static i2s_chan_handle_t i2s_example_init_pdm_tx(void)
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{
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i2s_chan_handle_t tx_chan; // I2S tx channel handler
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/* Setp 1: Determine the I2S channel configuration and allocate TX channel only
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* The default configuration can be generated by the helper macro,
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* it only requires the I2S controller id and I2S role,
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* but note that PDM channel can only be registered on I2S_NUM_0 */
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i2s_chan_config_t tx_chan_cfg = I2S_CHANNEL_DEFAULT_CONFIG(I2S_NUM_AUTO, I2S_ROLE_MASTER);
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tx_chan_cfg.auto_clear = true;
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ESP_ERROR_CHECK(i2s_new_channel(&tx_chan_cfg, &tx_chan, NULL));
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/* Step 2: Setting the configurations of PDM TX mode and initialize the TX channel
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* The slot configuration and clock configuration can be generated by the macros
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* These two helper macros is defined in 'i2s_pdm.h' which can only be used in PDM TX mode.
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* They can help to specify the slot and clock configurations for initialization or re-configuring */
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i2s_pdm_tx_config_t pdm_tx_cfg = {
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.clk_cfg = I2S_PDM_TX_CLK_DEFAULT_CONFIG(EXAMPLE_PDM_TX_FREQ_HZ),
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/* The data bit-width of PDM mode is fixed to 16 */
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.slot_cfg = I2S_PDM_TX_SLOT_DEFAULT_CONFIG(I2S_DATA_BIT_WIDTH_16BIT, I2S_SLOT_MODE_MONO),
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.gpio_cfg = {
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.clk = EXAMPLE_PDM_TX_CLK_IO,
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.dout = EXAMPLE_PDM_TX_DOUT_IO,
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.invert_flags = {
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.clk_inv = false,
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},
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},
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};
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ESP_ERROR_CHECK(i2s_channel_init_pdm_tx_mode(tx_chan, &pdm_tx_cfg));
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/* Step 3: Enable the tx channel before writing data */
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ESP_ERROR_CHECK(i2s_channel_enable(tx_chan));
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return tx_chan;
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}
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void i2s_example_pdm_tx_task(void *args)
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{
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int16_t *w_buf = (int16_t *)calloc(1, EXAMPLE_BUFF_SIZE);
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assert(w_buf);
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i2s_chan_handle_t tx_chan = i2s_example_init_pdm_tx();
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size_t w_bytes = 0;
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uint8_t cnt = 0; // The current index of the song
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uint8_t tone_select = 0; // To selecting the tone level
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printf("Playing %s `twinkle twinkle little star`\n", tone_name[tone_select]);
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while (1) {
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int tone_point = EXAMPLE_SINE_WAVE_LEN(tone[tone_select][song[cnt]-1]);
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/* Generate the tone buffer */
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for (int i = 0; i < tone_point; i++) {
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w_buf[i] = (int16_t)((sin(2 * (float)i * CONST_PI / tone_point)) * EXAMPLE_WAVE_AMPLITUDE);
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}
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for (int tot_bytes = 0; tot_bytes < EXAMPLE_BYTE_NUM_EVERY_TONE * rhythm[cnt % 7]; tot_bytes += w_bytes) {
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/* Play the tone */
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if (i2s_channel_write(tx_chan, w_buf, tone_point * sizeof(int16_t), &w_bytes, 1000) != ESP_OK) {
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printf("Write Task: i2s write failed\n");
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}
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}
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cnt++;
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/* If finished playing, switch the tone level */
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if (cnt == sizeof(song)) {
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cnt = 0;
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tone_select++;
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tone_select %= 3;
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printf("Playing %s `twinkle twinkle little star`\n", tone_name[tone_select]);
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}
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/* Gap between the tones */
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vTaskDelay(15);
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}
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free(w_buf);
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vTaskDelete(NULL);
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}
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