mirror of
https://github.com/espressif/esp-idf.git
synced 2024-10-05 20:47:46 -04:00
1f055d28b8
1. Modify I2S DAC built-in mode settings 2. Add I2S pdm mode 3. Correct I2S signal index in full-duplex mode 4. Modify dac output function 5. Add dac pad init functions 6. Modify DAC documentation 7. Add i2s_set_dac_mode API
137 lines
3.9 KiB
ReStructuredText
137 lines
3.9 KiB
ReStructuredText
I2S
|
|
===
|
|
|
|
Overview
|
|
--------
|
|
|
|
ESP32 contains two I2S peripherals. These peripherals can be configured to input and output sample data via the I2S driver.
|
|
|
|
The I2S peripheral supports DMA meaning it can stream sample data without requiring each sample to be read or written by the CPU.
|
|
|
|
I2S output can also be routed directly to the Digital/Analog Converter output channels (GPIO 25 & GPIO 26) to produce analog output directly, rather than via an external I2S codec.
|
|
|
|
Application Example
|
|
-------------------
|
|
|
|
A full I2S example is available in esp-idf: :example:`peripherals/i2s`.
|
|
|
|
Short example of I2S configuration::
|
|
|
|
#include "driver/i2s.h"
|
|
#include "freertos/queue.h"
|
|
|
|
static const int i2s_num = 0; // i2s port number
|
|
|
|
static const i2s_config_t i2s_config = {
|
|
.mode = I2S_MODE_MASTER | I2S_MODE_TX,
|
|
.sample_rate = 44100,
|
|
.bits_per_sample = 16,
|
|
.channel_format = I2S_CHANNEL_FMT_RIGHT_LEFT,
|
|
.communication_format = I2S_COMM_FORMAT_I2S | I2S_COMM_FORMAT_I2S_MSB,
|
|
.intr_alloc_flags = ESP_INTR_FLAG_LEVEL1, // high interrupt priority
|
|
.dma_buf_count = 8,
|
|
.dma_buf_len = 64
|
|
};
|
|
|
|
static const i2s_pin_config_t pin_config = {
|
|
.bck_io_num = 26,
|
|
.ws_io_num = 25,
|
|
.data_out_num = 22,
|
|
.data_in_num = I2S_PIN_NO_CHANGE
|
|
};
|
|
|
|
...
|
|
|
|
i2s_driver_install(i2s_num, &i2s_config, 0, NULL); //install and start i2s driver
|
|
|
|
i2s_set_pin(i2s_num, &pin_config);
|
|
|
|
i2s_set_sample_rates(i2s_num, 22050); //set sample rates
|
|
|
|
i2s_driver_uninstall(i2s_num); //stop & destroy i2s driver
|
|
|
|
Short example configuring I2S to use internal DAC for analog output::
|
|
|
|
#include "driver/i2s.h"
|
|
#include "freertos/queue.h"
|
|
|
|
static const int i2s_num = 0; // i2s port number
|
|
|
|
static const i2s_config_t i2s_config = {
|
|
.mode = I2S_MODE_MASTER | I2S_MODE_TX | I2S_MODE_DAC_BUILT_IN,
|
|
.sample_rate = 44100,
|
|
.bits_per_sample = 16, /* the DAC module will only take the 8bits from MSB */
|
|
.channel_format = I2S_CHANNEL_FMT_RIGHT_LEFT,
|
|
.communication_format = I2S_COMM_FORMAT_I2S_MSB,
|
|
.intr_alloc_flags = ESP_INTR_FLAG_LEVEL1, // high interrupt priority
|
|
.dma_buf_count = 8,
|
|
.dma_buf_len = 64
|
|
};
|
|
|
|
...
|
|
|
|
i2s_driver_install(i2s_num, &i2s_config, 0, NULL); //install and start i2s driver
|
|
|
|
i2s_set_pin(i2s_num, NULL); //for internal DAC, this will enable both of the internal channels
|
|
|
|
//You can call i2s_set_dac_mode to set built-in DAC output mode.
|
|
//i2s_set_dac_mode(I2S_DAC_CHANNEL_BOTH_EN);
|
|
|
|
i2s_set_sample_rates(i2s_num, 22050); //set sample rates
|
|
|
|
i2s_driver_uninstall(i2s_num); //stop & destroy i2s driver
|
|
|
|
API Reference
|
|
-------------
|
|
|
|
Header Files
|
|
^^^^^^^^^^^^
|
|
|
|
* `components/driver/include/driver/i2s.h`
|
|
|
|
Data Structures
|
|
^^^^^^^^^^^^^^^
|
|
|
|
.. doxygenstruct:: i2s_config_t
|
|
:members:
|
|
.. doxygenstruct:: i2s_event_t
|
|
:members:
|
|
.. doxygenstruct:: i2s_pin_config_t
|
|
:members:
|
|
|
|
Macros
|
|
^^^^^^
|
|
|
|
.. doxygendefine:: I2S_PIN_NO_CHANGE
|
|
|
|
Enumerations
|
|
^^^^^^^^^^^^
|
|
|
|
.. doxygenenum:: i2s_bits_per_sample_t
|
|
.. doxygenenum:: i2s_comm_format_t
|
|
.. doxygenenum:: i2s_channel_fmt_t
|
|
.. doxygenenum:: pdm_sample_rate_ratio_t
|
|
.. doxygenenum:: pdm_pcm_conv_t
|
|
.. doxygenenum:: i2s_port_t
|
|
.. doxygenenum:: i2s_mode_t
|
|
.. doxygenenum:: i2s_event_type_t
|
|
.. doxygenenum:: i2s_dac_mode_t
|
|
|
|
Functions
|
|
^^^^^^^^^
|
|
|
|
.. doxygenfunction:: i2s_set_pin
|
|
.. doxygenfunction:: i2s_set_dac_mode
|
|
.. doxygenfunction:: i2s_driver_install
|
|
.. doxygenfunction:: i2s_driver_uninstall
|
|
.. doxygenfunction:: i2s_write_bytes
|
|
.. doxygenfunction:: i2s_read_bytes
|
|
.. doxygenfunction:: i2s_push_sample
|
|
.. doxygenfunction:: i2s_pop_sample
|
|
.. doxygenfunction:: i2s_set_sample_rates
|
|
.. doxygenfunction:: i2s_start
|
|
.. doxygenfunction:: i2s_stop
|
|
.. doxygenfunction:: i2s_zero_dma_buffer
|
|
|
|
|