python-spi

Note: python-spi is still under active development

Overview

A pure Python SPI interface using the Linux spidev device

Features

• Pure Python implementation. No C module to compile.
• Supports half-duplex reads and writes as well as full-duplex transfers.
• Exposes all available spidev interface options as properties.

Requirements

• spidev enabled in the kernel and (if necessary) the device tree.
• Write permissions to the /dev/spidevN.N device.
  • Some distributions have an 'spi' group for this purpose. If available, add this group to the user account and ensure the spidev device is group-writeable.
  • If no 'spi' group exists, a udev rule can be created to set the permissions of the spidev device.
  • As a last resort, running the python script as root should allow access to the spidev. Note This is not recommended. Use the 'spi' group or udev rules whenever possible.

Example

import spi
spi = SPI("/dev/spidev1.0")
spi.mode = SPI.MODE_0
spi.bits_per_word = 8
spi.speed = 500000
received = spi.transfer([0x11, 0x22, 0xFF])
spi.write([0x12, 0x34, 0xAB, 0xCD])
received = spi.read(10)