main.py

#!/usr/bin/python

import RPi.GPIO as GPIO
import time
import signal
import datetime
import os
from subprocess import check_output, call, Popen
from config import *
from mcp3551 import MCP3551
from mcp3001 import MCP3001
from mcp3008 import MCP3008

def draw_icon(layer, icon):
	Popen(PNGVIEWPATH + "/pngview -b 0 -l " + layer + " -x " + str(ICONX) + " -y " + str(ICONY) + " " + ICONPATH + "/" + icon + " &", cwd=os.path.dirname(os.path.realpath(__file__)), shell=True)

def change_icon(percent):
	if (ICON != 1):
		return

	draw_icon("3000" + percent, "battery" + percent + ".png")

	if (DEBUGMSG == 1):
		print("Changed battery icon to " + percent + "%")

	out = check_output("ps aux | grep pngview | awk '{ print $2 }'", shell=True)
	nums = out.split('\n')
	i = 0

	for num in nums:
		i += 1
		if (i == 1):
			call("sudo kill " + num, shell=True)

def change_led(led):
	if (LEDS != 1):
		return

	if (led == "green"):
		GPIO.output(GOODVOLTPIN, GPIO.HIGH)
		GPIO.output(LOWVOLTPIN, GPIO.LOW)

		printf("Changed green LED to on, red LED to off")
	elif (led == "red"):
		GPIO.output(GOODVOLTPIN, GPIO.LOW)
		GPIO.output(LOWVOLTPIN, GPIO.HIGH)

		printf("Changed green LED to off, red LED to on")

def end_process(signalnum = None, handler = None):
	GPIO.cleanup()
	call("sudo killall pngview", shell=True);
	exit(0)

status = 0

# prepare handlers for process exit
signal.signal(signal.SIGTERM, end_process)
signal.signal(signal.SIGINT, end_process)

# initialize ADC
if (ADC == "MCP3551"):
	adc = MCP3551(SPIMISO, SPIMOSI, SPICLK, SPICS)
elif (ADC == "MCP3001"):
	adc = MCP3001(SPIMISO, SPIMOSI, SPICLK, SPICS)
elif (ADC == "MCP3008"):
	adc = MCP3008(SPIMISO, SPIMOSI, SPICLK, SPICS, ADCCHANNEL)
else:
	print("Unknown ADC type " + str(ADC) + "! Please set ADC in config.py to one of the supported types.")
	exit(0)

adc.setup_pins()

SVOLT100 = VOLT100 * HIGHRESVAL / (LOWRESVAL + HIGHRESVAL)
SVOLT75 = VOLT75 * HIGHRESVAL / (LOWRESVAL + HIGHRESVAL)
SVOLT50 = VOLT50 * HIGHRESVAL / (LOWRESVAL + HIGHRESVAL)
SVOLT25 = VOLT25 * HIGHRESVAL / (LOWRESVAL + HIGHRESVAL)
SVOLT0 = VOLT0 * HIGHRESVAL / (LOWRESVAL + HIGHRESVAL)

ADC100 = SVOLT100 / (ADCVREF / adc.get_resolution())
ADC75 = SVOLT75 / (ADCVREF / adc.get_resolution())
ADC50 = SVOLT50 / (ADCVREF / adc.get_resolution())
ADC25 = SVOLT25 / (ADCVREF / adc.get_resolution())
ADC0 = SVOLT0 / (ADCVREF / adc.get_resolution())

if (DEBUGMSG == 1):
	print("Batteries 100% voltage:		" + str(VOLT100))
	print("Batteries 75% voltage:		" + str(VOLT75))
	print("Batteries 50% voltage:		" + str(VOLT50))
	print("Batteries 25% voltage:		" + str(VOLT25))
	print("Batteries dangerous voltage:	" + str(VOLT0))
	print("ADC 100% value:			" + str(ADC100))
	print("ADC 75% value:			" + str(ADC75))
	print("ADC 50% value:			" + str(ADC50))
	print("ADC 25% value:			" + str(ADC25))
	print("ADC dangerous voltage value:	" + str(ADC0))

# setup LED pins
if (LEDS == 1):
	GPIO.setmode(GPIO.BOARD)
	GPIO.setup(GOODVOLTPIN, GPIO.OUT)
	GPIO.setup(LOWVOLTPIN, GPIO.OUT)
	GPIO.output(GOODVOLTPIN, GPIO.LOW)
	GPIO.output(LOWVOLTPIN, GPIO.LOW)

draw_icon("299999", "blank.png")

count = 0

if (CSVOUT == 1):
	print("#;Timestamp;Date and time;Raw value;Voltage")

while True:
	# measure three times and use the average
	ret1 = adc.read_value()
	ret2 = adc.read_value()
	ret3 = adc.read_value()
	ret = (ret1 + ret2 + ret3) / 3
	voltage = ((HIGHRESVAL + LOWRESVAL) * ret * (ADCVREF / adc.get_resolution())) / HIGHRESVAL

	if (CSVOUT == 1):
		print(str(count) + ";" + str(time.time()) + ";" + str(datetime.datetime.now()) + ";" + str(ret) + ";" + str(voltage))

	if (DEBUGMSG == 1):
		print("ADC value: " + str(ret) + " (" + str(voltage) + " V)")

	if (ret < ADC0):
		if (status != 0):
			change_icon("0")
			change_led("red")

		status = 0
	elif (ret < ADC25):
		if (status != 25):
			change_led("red")
			change_icon("25")

		status = 25
	elif (ret < ADC50):
		if (status != 50):
			change_led("green")
			change_icon("50")

		status = 50
	elif (ret < ADC75):
		if (status != 75):
			change_led("green")
			change_icon("75")

		status = 75
	else:
		if (status != 100):
			change_led("green")
			change_icon("100")

		status = 100

	count += 1
	time.sleep(REFRESHRATE)