contrib-munin/plugins/system/read_serial_temperature

#!/usr/bin/env python
"""
Paul Wiegmans (p.wiegmans@bonhoeffer.nl)
2009 dec 18
This munin-node plugin reads a temperature value from a serial port,
provided by a Arduino with temperature sensor.
For details see: http://amber.bonhoeffer.nl/temperatuur/


Linux: "/dev/usb/ttyUSB[n]" or "/dev/ttyUSB[n]"
    first for for RedHat, second form for Debian.
    e.g. "/dev/usb/ttyUSB0"
"""

import sys, serial

# Open named port at "19200,8,N,1", 1s timeout::

def gettemperature():
	ser = serial.Serial('/dev/ttyUSB0', 9600, timeout=1)
	t = 0
	while t<1:
		line = ser.readline().strip()
		if line:
			temp = str(line.split(" ")[0]) # temperature in tenths celsius
			i = len(temp)-1
			temp = temp[:i]  # return only integer value (as a string)
			return temp
			t += 1
	ser.close()

# shamelessly copied from weather_temp_

if len(sys.argv) == 2 and sys.argv[1] == "autoconf":

  print "yes"

elif len(sys.argv) == 2 and sys.argv[1] == "config":

  print 'graph_title Temperatuur in de serverruimte'
  print 'graph_vlabel temperature in C'
  print 'graph_category sensors'
  print 'temperature.label temperature'
  print 'graph_info Dit is de temperatuur in het rek in de serverruimte B104'
  print 'graph_scale no'
  # lower limit 10, upper limit 50
  print 'graph_args --base 1000 -l 10 -u 50'

else:

  print 'temperature.value %s' % gettemperature()