2 ## This file is part of the sigrok project.
4 ## Copyright (C) 2012 Uwe Hermann <uwe@hermann-uwe.de>
6 ## This program is free software; you can redistribute it and/or modify
7 ## it under the terms of the GNU General Public License as published by
8 ## the Free Software Foundation; either version 2 of the License, or
9 ## (at your option) any later version.
11 ## This program is distributed in the hope that it will be useful,
12 ## but WITHOUT ANY WARRANTY; without even the implied warranty of
13 ## MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 ## GNU General Public License for more details.
16 ## You should have received a copy of the GNU General Public License
17 ## along with this program; if not, write to the Free Software
18 ## Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
21 # Melexis MLX90614 Infrared Thermometer protocol decoder
23 import sigrokdecode as srd
25 class Decoder(srd.Decoder):
29 longname = 'Melexis MLX90614'
30 desc = 'Infrared Thermometer protocol.'
33 outputs = ['mlx90614']
38 ['Celsius', 'Temperature in degrees Celsius'],
39 ['Kelvin', 'Temperature in Kelvin'],
42 def __init__(self, **kwargs):
43 self.state = 'IGNORE START REPEAT'
46 def start(self, metadata):
47 # self.out_proto = self.add(srd.OUTPUT_PROTO, 'mlx90614')
48 self.out_ann = self.add(srd.OUTPUT_ANN, 'mlx90614')
54 self.put(self.ss, self.es, self.out_ann, data)
56 # Quick hack implementation! This needs to be improved a lot!
57 def decode(self, ss, es, data):
61 if self.state == 'IGNORE START REPEAT':
62 if cmd != 'START REPEAT':
64 self.state = 'IGNORE ADDRESS WRITE'
65 elif self.state == 'IGNORE ADDRESS WRITE':
66 if cmd != 'ADDRESS WRITE':
68 self.state = 'GET TEMPERATURE'
69 elif self.state == 'GET TEMPERATURE':
70 if cmd != 'DATA WRITE':
72 if len(self.data) == 0:
73 self.data.append(databyte)
75 elif len(self.data) == 1:
76 self.data.append(databyte)
79 kelvin = (self.data[0] | (self.data[1] << 8)) * 0.02
80 celsius = kelvin - 273.15
81 self.putx([0, ['Temperature: %3.2f °C' % celsius]])
82 self.putx([1, ['Temperature: %3.2f K' % kelvin]])
83 self.state = 'IGNORE START REPEAT'
86 raise Exception('Invalid state: %s' % self.state)