feature(i2s): add i2s driver

This commit is contained in:
XiongYu
2019-03-25 10:47:20 +08:00
parent d913340f00
commit cac248c42f
11 changed files with 1427 additions and 7 deletions

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#
# This is a project Makefile. It is assumed the directory this Makefile resides in is a
# project subdirectory.
#
PROJECT_NAME := i2s
include $(IDF_PATH)/make/project.mk

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# I2S Example
(See the README.md file in the upper level 'examples' directory for more information about examples.)
In this example, we generate a 100Hz triangle and sine wave and send it out from left and right channels at a sample rate of 36kHz through the I2S bus.
## How to Use Example
### Hardware Required
* A development board with ESP8266 SoC (e.g., ESP8266-DevKitC, etc.)
* A USB cable for power supply and programming
### Configure the Project
```
make menuconfig
```
* Set serial port under Serial Flasher Options.
### Build and Flash
Build the project and flash it to the board, then run monitor tool to view serial output:
```
make -j4 flash monitor
```
(To exit the serial monitor, type ``Ctrl-]``.)
See the Getting Started Guide for full steps to configure and use ESP-IDF to build projects.
## Example Output
Running this example, you will see the Bits per Sample changes every 5 seconds after you have run this example. You can use `i2s_set_clk` to change the Bits per Sample and the Sample Rate. The output log can be seen below:
```
Test bits=24 free mem=78188, written data=2880
I (5655) i2s: DMA Malloc info, datalen=blocksize=480, dma_buf_count=6
Test bits=16 free mem=78188, written data=1440
I (10735) i2s: DMA Malloc info, datalen=blocksize=240, dma_buf_count=6
Test bits=24 free mem=78188, written data=2880
I (15835) i2s: DMA Malloc info, datalen=blocksize=480, dma_buf_count=6
Test bits=16 free mem=78188, written data=1440
I (20915) i2s: DMA Malloc info, datalen=blocksize=240, dma_buf_count=6
```
If you have a logic analyzer, you can use a logic analyzer to grab online data. The following table describes the pins we use by default (Note that you can also use other pins for the same purpose).
| pin name| function | gpio_num |
|:---:|:---:|:---:|
| MCLK|main clock | GPIO_NUM_4 |
| WS |word select| GPIO_NUM_2 |
| SCK |continuous serial clock| GPIO_NUM_15 |
| SD |serial data| GPIO_NUM_3 |
## Troubleshooting
* Program upload failure
* Hardware connection is not correct: run `make monitor`, and reboot your board to see if there are any output logs.
* The baud rate for downloading is too high: lower your baud rate in the `menuconfig` menu, and try again.
For any technical queries, please open an [issue](https://github.com/espressif/ESP8266_RTOS_SDK/issues) on GitHub. We will get back to you soon.

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#
# Main Makefile. This is basically the same as a component makefile.
#

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/* I2S Example
This example code will output 100Hz sine wave and triangle wave to 2-channel of I2S driver
Every 5 seconds, it will change bits_per_sample [16, 24, 32] for i2s data
This example code is in the Public Domain (or CC0 licensed, at your option.)
Unless required by applicable law or agreed to in writing, this
software is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR
CONDITIONS OF ANY KIND, either express or implied.
*/
#include <stdio.h>
#include <math.h>
#include "freertos/FreeRTOS.h"
#include "freertos/task.h"
#include "driver/i2s.h"
#include "esp_system.h"
#include "esp8266/pin_mux_register.h"
#define SAMPLE_RATE (36000)
#define I2S_NUM (0)
#define WAVE_FREQ_HZ (100)
#define PI (3.14159265)
#define I2S_MCLK_EN (1)
#define I2S_BCK_EN (1)
#define I2S_WS_EN (1)
#define I2S_DO_EN (1)
#define I2S_DI_EN (0)
#define SAMPLE_PER_CYCLE (SAMPLE_RATE/WAVE_FREQ_HZ)
static void setup_triangle_sine_waves(int bits)
{
int *samples_data = malloc(((bits + 8) / 16) * SAMPLE_PER_CYCLE * 4);
unsigned int i, sample_val;
double sin_float, triangle_float, triangle_step = (double) pow(2, bits) / SAMPLE_PER_CYCLE;
size_t i2s_bytes_write = 0;
printf("\r\nTest bits=%d free mem=%d, written data=%d\n", bits, esp_get_free_heap_size(), ((bits + 8) / 16)*SAMPLE_PER_CYCLE * 4);
triangle_float = -(pow(2, bits) / 2 - 1);
for (i = 0; i < SAMPLE_PER_CYCLE; i++) {
sin_float = sin(i * PI / 180.0);
if (sin_float >= 0) {
triangle_float += triangle_step;
} else {
triangle_float -= triangle_step;
}
sin_float *= (pow(2, bits) / 2 - 1);
if (bits == 16) {
sample_val = 0;
sample_val += (short)triangle_float;
sample_val = sample_val << 16;
sample_val += (short) sin_float;
samples_data[i] = sample_val;
} else if (bits == 24) { //1-bytes unused
samples_data[i * 2] = ((int) triangle_float) << 8;
samples_data[i * 2 + 1] = ((int) sin_float) << 8;
} else {
samples_data[i * 2] = ((int) triangle_float);
samples_data[i * 2 + 1] = ((int) sin_float);
}
}
i2s_set_clk(I2S_NUM, SAMPLE_RATE, bits, 2);
i2s_write(I2S_NUM, samples_data, ((bits + 8) / 16)*SAMPLE_PER_CYCLE * 4, &i2s_bytes_write, 100);
free(samples_data);
}
void app_main()
{
// for 36Khz sample rates, we create 100Hz sine wave, every cycle need 36000/100 = 360 samples (4-bytes or 8-bytes each sample)
// depend on bits_per_sample
// using 6 buffers, we need 60-samples per buffer
// if 2-channels, 16-bit each channel, total buffer is 360*4 = 1440 bytes
// if 2-channels, 24-bit each channel, total buffer is 360*8 = 2880 bytes
i2s_config_t i2s_config = {
.mode = I2S_MODE_MASTER | I2S_MODE_TX, // Only TX
.sample_rate = SAMPLE_RATE,
.bits_per_sample = 16,
.channel_format = I2S_CHANNEL_FMT_RIGHT_LEFT, // 2-channels
.communication_format = I2S_COMM_FORMAT_I2S | I2S_COMM_FORMAT_I2S_MSB,
.dma_buf_count = 6,
.dma_buf_len = 60
};
i2s_pin_config_t pin_config = {
.bck_o_en = I2S_BCK_EN,
.ws_o_en = I2S_WS_EN,
.data_out_en = I2S_DO_EN,
.data_in_en = I2S_DI_EN
};
i2s_driver_install(I2S_NUM, &i2s_config, 0, NULL);
i2s_set_pin(I2S_NUM, &pin_config);
if (I2S_MCLK_EN) {
PIN_FUNC_SELECT(PERIPHS_IO_MUX_GPIO4_U, FUNC_CLK_XTAL);
}
int test_bits = 16;
while (1) {
setup_triangle_sine_waves(test_bits);
vTaskDelay(5000 / portTICK_RATE_MS);
test_bits += 8;
if (test_bits > 24) {
test_bits = 16;
}
}
}