Introduction

CircuitPython library for the Maxim DS1841 I2C Logarithmic Resistor

Dependencies

This driver depends on:

• Adafruit CircuitPython
• Bus Device
• Register

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-ds1841

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

sudo pip3 install adafruit-circuitpython-ds1841

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-ds1841

Usage Example

from time import sleep
import board
import busio
import adafruit_ds1841
from analogio import AnalogIn

####### NOTE ################
# this example will not work with Blinka/rasberry Pi due to the lack of analog pins.
# Blinka and Raspberry Pi users should run the "ds1841_blinka_simpletest.py" example

# WIRING:
# 1 Wire connecting  VCC to RH to make a voltage divider using the
#   internal resistor between RH and RW
# 2 Wire connecting RW to A0

i2c = busio.I2C(board.SCL, board.SDA)
ds1841 = adafruit_ds1841.DS1841(i2c)
wiper_output = AnalogIn(board.A0)

while True:

    ds1841.wiper = 127
    print("Wiper set to %d"%ds1841.wiper)
    voltage = wiper_output.value
    voltage *= 3.3
    voltage /= 65535
    print("Wiper voltage: %.2f"%voltage)
    print("")
    sleep(1.0)

    ds1841.wiper = 0
    print("Wiper set to %d"%ds1841.wiper)
    voltage = wiper_output.value
    voltage *= 3.3
    voltage /= 65535
    print("Wiper voltage: %.2f"%voltage)
    print("")
    sleep(1.0)

    ds1841.wiper = 63
    print("Wiper set to %d"%ds1841.wiper)
    voltage = wiper_output.value
    voltage *= 3.3
    voltage /= 65535
    print("Wiper voltage: %.2f"%voltage)
    print("")
    sleep(1.0)

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.