nodemcu-firmware/docs/en/modules/dac.md

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# DAC Module
| Since | Origin / Contributor | Maintainer | Source |
| :----- | :-------------------- | :---------- | :------ |
| 2018-10-14 | [Arnim Läuger](https://github.com/devsaurus) | [Arnim Läuger](https://github.com/devsaurus) | [dac.c](../../../components/modules/dac.c)|
The DAC module provides access to the two built-in Digital to Analog Converters.
Each DAC is assigned to a dedicated GPIO:
- DAC channel 1 is attached to GPIO25
- DAC channel 2 is attached to GPIO26
The DACs are 8-bit, thus the output values are restricted to the range from 0 to 255.
## dac.disable()
Disables DAC output on the related GPIO.
#### Syntax
```lua
dac.disable(channel)
```
#### Parameters
- `channel` DAC channel, one of
- `dac.CHANNEL_1`
- `dac.CHANNEL_2`
#### Returns
`nil`
An error is thrown in case of invalid parameters or if the dac failed.
## dac.enable()
Enables DAC output on the related GPIO.
#### Syntax
```lua
dac.enable(channel)
```
#### Parameters
- `channel` DAC channel, one of
- `dac.CHANNEL_1`
- `dac.CHANNEL_2`
#### Returns
`nil`
An error is thrown in case of invalid parameters or if the dac failed.
## dac.write()
Sets the output value of the DAC.
#### Syntax
```lua
dac.write(channel, value)
```
#### Parameters
- `channel` DAC channel, one of
- `dac.CHANNEL_1`
- `dac.CHANNEL_2`
- `value` output value
#### Returns
`nil`
An error is thrown in case of invalid parameters or if the dac failed.