Python Joystick Mouse

mouse.py

#!/usr/bin/env python3

import spidev
import time
import struct

spi = spidev.SpiDev()
spi.open(0,0)
spi.max_speed_hz=100000
deadzone = 20
speed=.25

def spiChannel(channel):
      adc = spi.xfer2([1,(8+channel)<<4,0])
      data = ((adc[1]&3) << 8) + adc[2]
      return data

def write_report(button, x,y):
    with open('/dev/hidg0', 'rb+') as fd:
        report = struct.pack('bbb',button,x,y)
        fd.write(report)

def normalizeCoordinates(x, y):
    nx = ((x - 512) *-1) / 51
    ny = ((y - 512)) / 51
    return (round(nx * speed), round(ny * speed))

def normalizeButton(button):
    return 1 if button == 0 else 0

px = 0
py = 0

while True:

    btn = spiChannel(0)
    xval = spiChannel(2)
    yval = spiChannel(1)

    x, y = normalizeCoordinates(xval, yval)
    button = normalizeButton(btn)
    write_report(button,x,y)

    px = x if x > deadzone else 0
    py = y if y > deadzone else 0