OVMS3-idf/docs/en/api-reference/peripherals/dac.rst

Digital To Analog Converter
===========================

{IDF_TARGET_DAC_CH_1: default = "GPIO25", esp32 = "GPIO25", esp32s2 = "GPIO17"}
{IDF_TARGET_DAC_CH_2: default = "GPIO26", esp32 = "GPIO26", esp32s2 = "GPIO18"}

Overview
--------

{IDF_TARGET_NAME} has two 8-bit DAC (digital to analog converter) channels, connected to {IDF_TARGET_DAC_CH_1} (Channel 1) and {IDF_TARGET_DAC_CH_2} (Channel 2).


The DAC driver allows these channels to be set to arbitrary voltages.

The DAC channels can also be driven with DMA-style written sample data, via the :doc:`I2S driver <i2s>` when using the "built-in DAC mode".

For other analog output options, see the :doc:`Sigma-delta Modulation module <sigmadelta>` and the :doc:`LED Control module <ledc>`. Both these modules produce high frequency PWM output, which can be hardware low-pass filtered in order to generate a lower frequency analog output.


Application Example
-------------------

Setting DAC channel 1 ({IDF_TARGET_DAC_CH_1}) voltage to approx 0.78 of VDD_A voltage (VDD * 200 / 255). For VDD_A 3.3V, this is 2.59V::

  #include <driver/dac.h>

  ...

      dac_output_enable(DAC_CHANNEL_1);
      dac_output_voltage(DAC_CHANNEL_1, 200);

API Reference
-------------

.. include-build-file:: inc/dac.inc

GPIO Lookup Macros
^^^^^^^^^^^^^^^^^^
Some useful macros can be used to specified the GPIO number of a DAC channel, or vice versa.
e.g.

1. ``DAC_CHANNEL_1_GPIO_NUM`` is the GPIO number of channel 1 ({IDF_TARGET_DAC_CH_1});
2. ``DAC_{IDF_TARGET_DAC_CH_2}_CHANNEL`` is the channel number of GPIO 26 (channel 2).

.. include-build-file:: inc/dac_channel.inc
docs: Add missing peripheral driver docs (ADC, DAC, RTC I/O, I2S) 2017-02-16 02:59:50 +00:00			`Digital To Analog Converter`
			`===========================`

doc: updated peripherals api-reference for s2 2019-12-13 03:49:10 +00:00			`{IDF_TARGET_DAC_CH_1: default = "GPIO25", esp32 = "GPIO25", esp32s2 = "GPIO17"}`
			`{IDF_TARGET_DAC_CH_2: default = "GPIO26", esp32 = "GPIO26", esp32s2 = "GPIO18"}`

docs: Add missing peripheral driver docs (ADC, DAC, RTC I/O, I2S) 2017-02-16 02:59:50 +00:00			`Overview`
			`--------`

doc: updated peripherals api-reference for s2 2019-12-13 03:49:10 +00:00			`{IDF_TARGET_NAME} has two 8-bit DAC (digital to analog converter) channels, connected to {IDF_TARGET_DAC_CH_1} (Channel 1) and {IDF_TARGET_DAC_CH_2} (Channel 2).`
doc: Update English pages with generic target name 2019-12-09 03:01:09 +00:00

docs: Add missing peripheral driver docs (ADC, DAC, RTC I/O, I2S) 2017-02-16 02:59:50 +00:00
			`The DAC driver allows these channels to be set to arbitrary voltages.`

			The DAC channels can also be driven with DMA-style written sample data, via the :doc:`I2S driver <i2s>` when using the "built-in DAC mode".

			For other analog output options, see the :doc:`Sigma-delta Modulation module <sigmadelta>` and the :doc:`LED Control module <ledc>`. Both these modules produce high frequency PWM output, which can be hardware low-pass filtered in order to generate a lower frequency analog output.


			`Application Example`
			`-------------------`

doc: updated peripherals api-reference for s2 2019-12-13 03:49:10 +00:00			`Setting DAC channel 1 ({IDF_TARGET_DAC_CH_1}) voltage to approx 0.78 of VDD_A voltage (VDD * 200 / 255). For VDD_A 3.3V, this is 2.59V::`
docs: Add missing peripheral driver docs (ADC, DAC, RTC I/O, I2S) 2017-02-16 02:59:50 +00:00
			`#include <driver/dac.h>`

			`...`

Driver update: I2S pdm and built-in DAC 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 2017-05-03 10:55:52 +00:00			`dac_output_enable(DAC_CHANNEL_1);`
			`dac_output_voltage(DAC_CHANNEL_1, 200);`
docs: Add missing peripheral driver docs (ADC, DAC, RTC I/O, I2S) 2017-02-16 02:59:50 +00:00
			`API Reference`
			`-------------`

docs: add new top-level docs builder that builds docs for a single chip 2019-11-13 03:46:16 +00:00			`.. include-build-file:: inc/dac.inc`
docs: Add missing peripheral driver docs (ADC, DAC, RTC I/O, I2S) 2017-02-16 02:59:50 +00:00
feat(global): add macros for GPIO->channel lookup including: macros for dac, adc, touch, rtc_gpio, uart and clk_out. TW#13970 2017-08-29 07:52:04 +00:00			`GPIO Lookup Macros`
			`^^^^^^^^^^^^^^^^^^`
			`Some useful macros can be used to specified the GPIO number of a DAC channel, or vice versa.`
			`e.g.`

doc: updated peripherals api-reference for s2 2019-12-13 03:49:10 +00:00			1. ``DAC_CHANNEL_1_GPIO_NUM`` is the GPIO number of channel 1 ({IDF_TARGET_DAC_CH_1});
			2. ``DAC_{IDF_TARGET_DAC_CH_2}_CHANNEL`` is the channel number of GPIO 26 (channel 2).
feat(global): add macros for GPIO->channel lookup including: macros for dac, adc, touch, rtc_gpio, uart and clk_out. TW#13970 2017-08-29 07:52:04 +00:00
docs: add new top-level docs builder that builds docs for a single chip 2019-11-13 03:46:16 +00:00			`.. include-build-file:: inc/dac_channel.inc`