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CircuitPython Library for PCF8591 ADC+DAC Combo

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adafruit/Adafruit_CircuitPython_PCF8591

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Introduction

Documentation Status Discord Build Status Code Style: Black

ADC+DAC Combo

Dependencies

This driver depends on:

Please ensure all dependencies are available on the CircuitPython filesystem. This is easily achieved by downloading the Adafruit library and driver bundle.

Installing from PyPI

On supported GNU/Linux systems like the Raspberry Pi, you can install the driver locally from PyPI. To install for current user:

pip3 install adafruit-circuitpython-pcf8591

To install system-wide (this may be required in some cases):

sudo pip3 install adafruit-circuitpython-pcf8591

To install in a virtual environment in your current project:

mkdir project-name && cd project-name
python3 -m venv .venv
source .venv/bin/activate
pip3 install adafruit-circuitpython-pcf8591

Usage Example

import time
import board

import adafruit_pcf8591.pcf8591 as PCF
from adafruit_pcf8591.analog_in import AnalogIn
from adafruit_pcf8591.analog_out import AnalogOut

############# AnalogOut & AnalogIn Example ##########################
#
# This example shows how to use the included AnalogIn and AnalogOut
# classes to set the internal DAC to output a voltage and then measure
# it with the first ADC channel.
#
# Wiring:
# Connect the DAC output to the first ADC channel, in addition to the
# normal power and I2C connections
#
#####################################################################
i2c = board.I2C()
pcf = PCF.PCF8591(i2c)

pcf_in_0 = AnalogIn(pcf, PCF.A0)
pcf_out = AnalogOut(pcf, PCF.OUT)

while True:

    print("Setting out to ", 65535)
    pcf_out.value = 65535
    raw_value = pcf_in_0.value
    scaled_value = (raw_value / 65535) * pcf_in_0.reference_voltage

    print("Pin 0: %0.2fV" % (scaled_value))
    print("")
    time.sleep(1)

Documentation

API documentation for this library can be found on Read the Docs.

For information on building library documentation, please check out this guide.

Contributing

Contributions are welcome! Please read our Code of Conduct before contributing to help this project stay welcoming.