Introduction

A library for adding bitbang I2C and SPI to CircuitPython without the built-in bitbangio module. The interface is intended to be the same as bitbangio and therefore there is no bit order or chip select functionality. If your board supports bitbangio, it is recommended to use that instead as the timing should be more reliable.

Dependencies

This driver depends on:

Adafruit CircuitPython

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-bitbangio

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

sudo pip3 install adafruit-circuitpython-bitbangio

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-bitbangio

Usage Example

"""
This example is for demonstrating how to retrieving the
board ID from a BME280, which is stored in register 0xD0.
It should return a result of [96]
"""

import board
import digitalio
import adafruit_bitbangio as bitbangio

# Change these to the actual connections
SCLK_PIN = board.D6
MOSI_PIN = board.D17
MISO_PIN = board.D18
CS_PIN = board.D5

cs = digitalio.DigitalInOut(CS_PIN)
cs.switch_to_output(value=True)

spi = bitbangio.SPI(SCLK_PIN, MOSI=MOSI_PIN, MISO=MISO_PIN)
cs.value = 0
while not spi.try_lock():
    pass
spi.write([0xD0])
data = [0x00]
spi.readinto(data)
spi.unlock()
cs.value = 1
print("Result is {}".format(data))

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.