> ## Documentation Index
> Fetch the complete documentation index at: https://mintlify.com/wokwi/wokwi-docs/llms.txt
> Use this file to discover all available pages before exploring further.

# Analog API

> Read and write analog voltages on custom chip pins

## pin\_adc\_read

```c theme={null}
float pin_adc_read(pin_t pin)
```

Measures the current voltage on the given pin, and returns it. The pin must be set to `ANALOG` mode, otherwise the return value of this function is undefined.

<Note>
  Wokwi is a digital simulator with basic analog support, so there is currently very limited analog simulation. Some parts which support analog output include the [potentiometer](../parts/wokwi-slide-potentiometer), [NTC temperature sensor](../parts/wokwi-ntc-temperature-sensor), [photoresistor](../parts/wokwi-photoresistor-sensor), and [analog joystick](../parts/wokwi-analog-joystick).
</Note>

## pin\_dac\_write

```c theme={null}
void pin_dac_write(pin_t pin, float voltage)
```

Sets the analog voltage on the given pin. Currently, the reference voltage for all the virtual ADCs is 5 volts (regardless of the MCU), so setting the voltage to 0 will return the minimum value, and setting the voltage to 5 will return the maximum value (that is 1023 on Arduino). This may change in the future.

This method can be called before setting the pin to `ANALOG` mode, but the voltage will only update once the pin mode is set to `ANALOG`.

## Simulator examples

* [Analog API chip example](https://wokwi.com/projects/330112801381024338) -- Simulates a 0-5V/0-ADC\_MAX voltage source. One float attribute and one analog output.
* [Dual Op-Amp chip example](https://wokwi.com/projects/409320061010147329) -- Simulates a dual Op-Amp with 4 analog inputs, 2 analog outputs, 2 float attributes.
* [R-C filter](https://wokwi.com/projects/409325290405496833) -- Simulates a low-pass R-C filter with 1 analog input, one analog output, and 4 attributes.
* [Signal generator and Scope](https://wokwi.com/projects/359331973918199809) -- Simulates a signal generator with 5 attribute inputs and 1 analog output, and a scope with 4 digital inputs, 4 analog inputs and 4 attribute inputs. Chip code for both in Wokwi tabs. ([Scope github](https://github.com/Dlloydev/Wokwi-Chip-Scope))