OVMS3-idf/examples/peripherals/i2s/README.md

# 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 ESP32 SoC (e.g., ESP32-DevKitC, ESP-WROVER-KIT, 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=293780, written data=2880
I2S: DMA Malloc info, datalen=blocksize=480, dma_buf_count=6
I2S: PLL_D2: Req RATE: 36000, real rate: 37878.000, BITS: 24, CLKM: 11, BCK: 8, MCLK: 13837837.838, SCLK: 1818144.000000, diva: 64, divb: 36

Test bits=32 free mem=292336, written data=2880
I2S: DMA Malloc info, datalen=blocksize=480, dma_buf_count=6
I2S: PLL_D2: Req RATE: 36000, real rate: 36764.000, BITS: 32, CLKM: 17, BCK: 4, MCLK: 9216921.692, SCLK: 2352896.000000, diva: 64, divb: 23

Test bits=16 free mem=293772, written data=1440
I2S: DMA Malloc info, datalen=blocksize=240, dma_buf_count=6
I2S: PLL_D2: Req RATE: 36000, real rate: 36764.000, BITS: 16, CLKM: 17, BCK: 8, MCLK: 9216921.692, SCLK: 1176448.000000, diva: 64, divb: 23
```

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 |
|:---:|:---:|:---:|
| WS  |word select| GPIO_NUM_25 |
| SCK |continuous serial clock| GPIO_NUM_26 |
| SD  |serial data| GPIO_NUM_22 |

## 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/esp-idf/issues) on GitHub. We will get back to you soon.
I2S: fixed support for 24 and 32-bits, fixed tx/rx at the same time and others in log: Add support 24, 32 bits @jxmao optimize i2s_zero_buffer @jxmao correct config support slave mode @jxmao correct setup pin support tx/rx at the same time Enhance pin power @jxmao add dynamic change number of channels remove nvs_init remove start log and enhance power pin setup using enum for i2s_channel and i2s_bits_per_sample, return ESP_ERR_INVALID_ARG when check params validate i2s_bits_per_sample and channel check tx & rx buffer before fill zero remove checking channel as @jxmao suggest limit dma buffer modify i2s pin back to gpio mux before configure gpio matrix, resolve github issue #512 Add support 24, 32 bits reduce push function Modify sample can test with 24, 32-bits Add i2s sample README Fixed i2s_set_clk got reset sometime can changes bit-wide while running Fix sample rate calculation for DAC mode from @jeroen modify example can change bits per sample every 5 seconds cleanup add comment for bytes_per_sample update as @angus suggestions Add i2s_set_clk api I2S driver bug fixed as following log: @jxmao optimize i2s_zero_buffer @jxmao correct config support slave mode @jxmao correct setup pin support tx/rx at the same time Enhance pin power @jxmao add dynamic change number of channels remove nvs_init remove start log and enhance power pin setup using enum for i2s_channel and i2s_bits_per_sample, return ESP_ERR_INVALID_ARG when check params validate i2s_bits_per_sample and channel check tx & rx buffer before fill zero remove checking channel as @jxmao suggest limit dma buffer modify i2s pin back to gpio mux before configure gpio matrix, resolve github issue #512 limit dma buffer to 4092 change gpio_matrix_*_check to inline function, remove some comments and rename test_i2s function to setup_triangle_sine_waves for change commit title 2017-02-06 06:11:11 +00:00			`# I2S Example`

doc(i2s): update README.md file of i2s related examples. 2018-06-29 08:21:31 +00:00			`(See the README.md file in the upper level 'examples' directory for more information about examples.)`
I2S: fixed support for 24 and 32-bits, fixed tx/rx at the same time and others in log: Add support 24, 32 bits @jxmao optimize i2s_zero_buffer @jxmao correct config support slave mode @jxmao correct setup pin support tx/rx at the same time Enhance pin power @jxmao add dynamic change number of channels remove nvs_init remove start log and enhance power pin setup using enum for i2s_channel and i2s_bits_per_sample, return ESP_ERR_INVALID_ARG when check params validate i2s_bits_per_sample and channel check tx & rx buffer before fill zero remove checking channel as @jxmao suggest limit dma buffer modify i2s pin back to gpio mux before configure gpio matrix, resolve github issue #512 Add support 24, 32 bits reduce push function Modify sample can test with 24, 32-bits Add i2s sample README Fixed i2s_set_clk got reset sometime can changes bit-wide while running Fix sample rate calculation for DAC mode from @jeroen modify example can change bits per sample every 5 seconds cleanup add comment for bytes_per_sample update as @angus suggestions Add i2s_set_clk api I2S driver bug fixed as following log: @jxmao optimize i2s_zero_buffer @jxmao correct config support slave mode @jxmao correct setup pin support tx/rx at the same time Enhance pin power @jxmao add dynamic change number of channels remove nvs_init remove start log and enhance power pin setup using enum for i2s_channel and i2s_bits_per_sample, return ESP_ERR_INVALID_ARG when check params validate i2s_bits_per_sample and channel check tx & rx buffer before fill zero remove checking channel as @jxmao suggest limit dma buffer modify i2s pin back to gpio mux before configure gpio matrix, resolve github issue #512 limit dma buffer to 4092 change gpio_matrix_*_check to inline function, remove some comments and rename test_i2s function to setup_triangle_sine_waves for change commit title 2017-02-06 06:11:11 +00:00
doc(i2s): update README.md file of i2s related examples. 2018-06-29 08:21:31 +00:00			`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.`
I2S: fixed support for 24 and 32-bits, fixed tx/rx at the same time and others in log: Add support 24, 32 bits @jxmao optimize i2s_zero_buffer @jxmao correct config support slave mode @jxmao correct setup pin support tx/rx at the same time Enhance pin power @jxmao add dynamic change number of channels remove nvs_init remove start log and enhance power pin setup using enum for i2s_channel and i2s_bits_per_sample, return ESP_ERR_INVALID_ARG when check params validate i2s_bits_per_sample and channel check tx & rx buffer before fill zero remove checking channel as @jxmao suggest limit dma buffer modify i2s pin back to gpio mux before configure gpio matrix, resolve github issue #512 Add support 24, 32 bits reduce push function Modify sample can test with 24, 32-bits Add i2s sample README Fixed i2s_set_clk got reset sometime can changes bit-wide while running Fix sample rate calculation for DAC mode from @jeroen modify example can change bits per sample every 5 seconds cleanup add comment for bytes_per_sample update as @angus suggestions Add i2s_set_clk api I2S driver bug fixed as following log: @jxmao optimize i2s_zero_buffer @jxmao correct config support slave mode @jxmao correct setup pin support tx/rx at the same time Enhance pin power @jxmao add dynamic change number of channels remove nvs_init remove start log and enhance power pin setup using enum for i2s_channel and i2s_bits_per_sample, return ESP_ERR_INVALID_ARG when check params validate i2s_bits_per_sample and channel check tx & rx buffer before fill zero remove checking channel as @jxmao suggest limit dma buffer modify i2s pin back to gpio mux before configure gpio matrix, resolve github issue #512 limit dma buffer to 4092 change gpio_matrix_*_check to inline function, remove some comments and rename test_i2s function to setup_triangle_sine_waves for change commit title 2017-02-06 06:11:11 +00:00
doc(i2s): update README.md file of i2s related examples. 2018-06-29 08:21:31 +00:00			`## How to Use Example`

			`### Hardware Required`

			`* A development board with ESP32 SoC (e.g., ESP32-DevKitC, ESP-WROVER-KIT, 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=293780, written data=2880`
			`I2S: DMA Malloc info, datalen=blocksize=480, dma_buf_count=6`
			`I2S: PLL_D2: Req RATE: 36000, real rate: 37878.000, BITS: 24, CLKM: 11, BCK: 8, MCLK: 13837837.838, SCLK: 1818144.000000, diva: 64, divb: 36`

			`Test bits=32 free mem=292336, written data=2880`
			`I2S: DMA Malloc info, datalen=blocksize=480, dma_buf_count=6`
			`I2S: PLL_D2: Req RATE: 36000, real rate: 36764.000, BITS: 32, CLKM: 17, BCK: 4, MCLK: 9216921.692, SCLK: 2352896.000000, diva: 64, divb: 23`

			`Test bits=16 free mem=293772, written data=1440`
			`I2S: DMA Malloc info, datalen=blocksize=240, dma_buf_count=6`
			`I2S: PLL_D2: Req RATE: 36000, real rate: 36764.000, BITS: 16, CLKM: 17, BCK: 8, MCLK: 9216921.692, SCLK: 1176448.000000, diva: 64, divb: 23`
			```

			`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 \|`
			`\|:---:\|:---:\|:---:\|`
			`\| WS \|word select\| GPIO_NUM_25 \|`
			`\| SCK \|continuous serial clock\| GPIO_NUM_26 \|`
			`\| SD \|serial data\| GPIO_NUM_22 \|`

			`## 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/esp-idf/issues) on GitHub. We will get back to you soon.`