svn.andrew.net.au/scripts/read-temperature.py

#!/usr/bin/python

###
# Program to read the temperature from a DLP-TEMP-G from a Linux computer
# http://www.dlpdesign.com/usb/temp.shtml
#
# Loosely based on Tim Jensen's program at
# http://www.jensens.org/tim/read-temperature.txt
#
# Copyright (c) 2007 Andrew Pollock <me@andrew.net.au>
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License along
# with this program; if not, write to the Free Software Foundation, Inc.,
# 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
#

import sys
try:
  import serial
except ImportError:
  print "This program requires pyserial,", \
    "try checking the python-serial package is installed"
  sys.exit(-1)

from optparse import OptionParser

def read_temperature(device, sensor):
  ser = serial.Serial(device, 9600, timeout=1)

  ser.write(SENSOR_QUERY_CMD[sensor])
  buf = ser.read(8)
  ser.close()

  temp = ord(buf[0]) | (ord(buf[1]) << 8)
  return temp

  
SENSOR_QUERY_CMD = (None, 'S', 'T', 'U')
USAGE = "usage: %prog [options] [action]"

parser = OptionParser(USAGE)
parser.add_option("-F", "--fahrenheit", action="store_false", 
  dest="use_celsius", help="Output temperature in degrees Fahrenheit", 
  default=False)
parser.add_option("-C", "--celsius", action="store_true", 
  dest="use_celsius", help="Output temperature in degrees Celsius", 
  default=True)
parser.add_option("-d", "--device", action="store", type="string",
  dest="device", help="device to communicate with", 
  default="/dev/ttyUSB0")
parser.add_option("-s", "--sensor", action="store", type="int",
  dest="sensor", help="sensor to query",
  default="1")
parser.add_option("--mrtg", action="store_true",
  dest="output_mrtg", help="Output decimal value suitable for MRTG",
  default=False)
(options, args) = parser.parse_args()

if not(options.sensor > 0 and options.sensor <= len(SENSOR_QUERY_CMD) - 1):
  parser.error("Invalid sensor")

try:
  temp = read_temperature(options.device, options.sensor)
except serial.SerialException, e:
  print "%s" % (e)
  sys.exit(1)

degrees = temp / 16.0

# The power-up temperature of the sensor is 85 degrees, which is fairly unlikely
# So if we get that temperature, try reading it again

if degrees == 85.0:
  try:
    temp = read_temperature(options.device, options.sensor)
  except serial.SerialException, e:
    print "%s" % (e)
    sys.exit(1)
  degrees = temp / 16.0

if (options.use_celsius):
  if (options.output_mrtg):
    print "%.0f" % degrees
  else:
    print "%.4f degrees Celsius" % degrees
else:
  degrees = (9.0/5.0) * degrees + 32.0
  if (options.output_mrtg):
    print "%.0f" % degrees
  else:
    print "%.4f degrees Fahrenheit" % degrees
1	apollock	18	#!/usr/bin/python
2
3			###
4			# Program to read the temperature from a DLP-TEMP-G from a Linux computer
5			# http://www.dlpdesign.com/usb/temp.shtml
6			#
7			# Loosely based on Tim Jensen's program at
8			# http://www.jensens.org/tim/read-temperature.txt
9			#
10			# Copyright (c) 2007 Andrew Pollock <me@andrew.net.au>
11			#
12			# This program is free software; you can redistribute it and/or modify
13			# it under the terms of the GNU General Public License as published by
14			# the Free Software Foundation; either version 2 of the License.
15			#
16			# This program is distributed in the hope that it will be useful,
17			# but WITHOUT ANY WARRANTY; without even the implied warranty of
18			# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
19			# GNU General Public License for more details.
20			#
21			# You should have received a copy of the GNU General Public License along
22			# with this program; if not, write to the Free Software Foundation, Inc.,
23			# 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
24			#
25
26	apollock	24	import sys
27	apollock	18	try:
28			import serial
29			except ImportError:
30			print "This program requires pyserial,", \
31			"try checking the python-serial package is installed"
32	apollock	24	sys.exit(-1)
33	apollock	18
34			from optparse import OptionParser
35
36	apollock	23	def read_temperature(device, sensor):
37			ser = serial.Serial(device, 9600, timeout=1)
38
39			ser.write(SENSOR_QUERY_CMD[sensor])
40			buf = ser.read(8)
41			ser.close()
42
43			temp = ord(buf[0]) \| (ord(buf[1]) << 8)
44			return temp
45
46
47	apollock	18	SENSOR_QUERY_CMD = (None, 'S', 'T', 'U')
48			USAGE = "usage: %prog [options] [action]"
49
50			parser = OptionParser(USAGE)
51			parser.add_option("-F", "--fahrenheit", action="store_false",
52			dest="use_celsius", help="Output temperature in degrees Fahrenheit",
53			default=False)
54			parser.add_option("-C", "--celsius", action="store_true",
55			dest="use_celsius", help="Output temperature in degrees Celsius",
56			default=True)
57			parser.add_option("-d", "--device", action="store", type="string",
58			dest="device", help="device to communicate with",
59			default="/dev/ttyUSB0")
60			parser.add_option("-s", "--sensor", action="store", type="int",
61			dest="sensor", help="sensor to query",
62			default="1")
63			parser.add_option("--mrtg", action="store_true",
64			dest="output_mrtg", help="Output decimal value suitable for MRTG",
65			default=False)
66			(options, args) = parser.parse_args()
67
68			if not(options.sensor > 0 and options.sensor <= len(SENSOR_QUERY_CMD) - 1):
69			parser.error("Invalid sensor")
70
71	apollock	22	try:
72	apollock	23	temp = read_temperature(options.device, options.sensor)
73	apollock	22	except serial.SerialException, e:
74			print "%s" % (e)
75			sys.exit(1)
76	apollock	18
77	apollock	23	degrees = temp / 16.0
78	apollock	18
79	apollock	23	# The power-up temperature of the sensor is 85 degrees, which is fairly unlikely
80			# So if we get that temperature, try reading it again
81	apollock	18
82	apollock	23	if degrees == 85.0:
83			try:
84			temp = read_temperature(options.device, options.sensor)
85			except serial.SerialException, e:
86			print "%s" % (e)
87			sys.exit(1)
88			degrees = temp / 16.0
89	apollock	18
90			if (options.use_celsius):
91			if (options.output_mrtg):
92			print "%.0f" % degrees
93			else:
94			print "%.4f degrees Celsius" % degrees
95			else:
96			degrees = (9.0/5.0) * degrees + 32.0
97			if (options.output_mrtg):
98			print "%.0f" % degrees
99			else:
100			print "%.4f degrees Fahrenheit" % degrees