Linux SysFS GPIO access via Python

This package offer Python classes to work with GPIO on Linux.

This work is based on @derekstavis amazing work, with minor changes made entirely for my own sake of learning experience.

System Requirements

As this package relies on modern techniques provided by Linux kernel, so your kernel version should support at least EPoll and SysFS interfaces.

How to use it

1. Install the package

pip install pysysfs-gpio

Example

# Import Twisted mainloop
from twisted.internet import reactor

# Import this package objects
from pysysfs.Controller import Controller
from pysysfs.const import OUTPUT, INPUT, RISING

# Refer to your chip GPIO numbers and set them this way - or referance your board from boards.py
controller = Controller()
controller.available_pins = [1, 2, 3, 4]

# Allocate a pin as Output signal
pin = controller.alloc_pin(1, OUTPUT)
pin.high()   # Sets pin to high logic level
pin.low()    # Sets pin to low logic level
pin.read()   # Reads pin logic level

# Allocate a pin as simple Input signal
pin = controller.alloc_pin(1, INPUT)
pin.read()   # Reads pin logic level

# Allocate a pin as level triggered Input signal
def pin_changed(number, state):
    print("Pin '%d' changed to %d state" % (number, state))

pin = controller.alloc_pin(1, INPUT, pin_changed, RISING)
pin.read()   # Reads pin logic level

3. Don't forget to start reactor loop!

    reactor.run()

LED blink example

from time import sleep

from pysysfs.boards import NANOPI_NEO_3
from pysysfs.const import OUTPUT
from pysysfs.Controller import Controller
from twisted.internet import reactor
from twisted.internet.task import LoopingCall

controller = Controller()
controller.available_pins = NANOPI_NEO_3

led = controller.alloc_pin(79, OUTPUT)


def blink():
    led.high()
    sleep(1)
    led.low()
    sleep(1)

# Main loop
lc = LoopingCall(blink)
lc.start(0.1)

reactor.run()