2 ## This file is part of the libsigrokdecode project.
4 ## Copyright (C) 2014 Gump Yang <gump.yang@gmail.com>
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, see <http://www.gnu.org/licenses/>.
20 import sigrokdecode as srd
23 class SamplerateError(Exception):
26 class Decoder(srd.Decoder):
31 desc = 'NEC infrared remote control protocol.'
37 {'id': 'ir', 'name': 'IR', 'desc': 'Data line'},
40 {'id': 'polarity', 'desc': 'Polarity', 'default': 'active-low',
41 'values': ('active-low', 'active-high')},
42 {'id': 'cd_freq', 'desc': 'Carrier Frequency', 'default': 0},
46 ('agc-pulse', 'AGC pulse'),
47 ('longpause', 'Long pause'),
48 ('shortpause', 'Short pause'),
49 ('stop-bit', 'Stop bit'),
50 ('leader-code', 'Leader code'),
52 ('addr-inv', 'Address#'),
54 ('cmd-inv', 'Command#'),
55 ('repeat-code', 'Repeat code'),
57 ('warning', 'Warning'),
60 ('bits', 'Bits', (0, 1, 2, 3, 4)),
61 ('fields', 'Fields', (5, 6, 7, 8, 9, 10)),
62 ('remote-vals', 'Remote', (11,)),
63 ('warnings', 'Warnings', (12,)),
67 self.put(self.ss_start, self.samplenum, self.out_ann, data)
70 self.put(self.ss_bit, self.samplenum, self.out_ann, data)
73 name = self.state.title()
74 d = {'ADDRESS': 6, 'ADDRESS#': 7, 'COMMAND': 8, 'COMMAND#': 9}
75 s = {'ADDRESS': ['ADDR', 'A'], 'ADDRESS#': ['ADDR#', 'A#'],
76 'COMMAND': ['CMD', 'C'], 'COMMAND#': ['CMD#', 'C#']}
77 self.putx([d[self.state], ['%s: 0x%02X' % (name, data),
78 '%s: 0x%02X' % (s[self.state][0], data),
79 '%s: 0x%02X' % (s[self.state][1], data), s[self.state][1]]])
81 def putstop(self, ss):
82 self.put(ss, ss + self.stop, self.out_ann,
83 [4, ['Stop bit', 'Stop', 'St', 'S']])
85 def putpause(self, p):
86 self.put(self.ss_start, self.ss_other_edge, self.out_ann,
87 [1, ['AGC pulse', 'AGC', 'A']])
88 idx = 2 if p == 'Long' else 3
89 self.put(self.ss_other_edge, self.samplenum, self.out_ann,
90 [idx, [p + ' pause', '%s-pause' % p[0], '%sP' % p[0], 'P']])
93 dev = address.get(self.addr, 'Unknown device')
94 buttons = command.get(self.addr, None)
96 btn = ['Unknown', 'Unk']
98 btn = buttons.get(self.cmd, ['Unknown', 'Unk'])
99 self.put(self.ss_remote, self.ss_bit + self.stop, self.out_ann,
100 [11, ['%s: %s' % (dev, btn[0]), '%s: %s' % (dev, btn[1]),
108 self.ss_bit = self.ss_start = self.ss_other_edge = self.ss_remote = 0
109 self.data = self.count = self.active = None
110 self.addr = self.cmd = None
113 self.out_ann = self.register(srd.OUTPUT_ANN)
115 def metadata(self, key, value):
116 if key == srd.SRD_CONF_SAMPLERATE:
117 self.samplerate = value
118 self.tolerance = 0.05 # +/-5%
119 self.lc = int(self.samplerate * 0.0135) - 1 # 13.5ms
120 self.rc = int(self.samplerate * 0.01125) - 1 # 11.25ms
121 self.dazero = int(self.samplerate * 0.001125) - 1 # 1.125ms
122 self.daone = int(self.samplerate * 0.00225) - 1 # 2.25ms
123 self.stop = int(self.samplerate * 0.000652) - 1 # 0.652ms
125 def compare_with_tolerance(self, measured, base):
126 return (measured >= base * (1 - self.tolerance)
127 and measured <= base * (1 + self.tolerance))
129 def handle_bit(self, tick):
131 if self.compare_with_tolerance(tick, self.dazero):
133 elif self.compare_with_tolerance(tick, self.daone):
136 self.putb([0, ['%d' % ret]])
137 self.data |= (ret << self.count) # LSB-first
138 self.count = self.count + 1
139 self.ss_bit = self.samplenum
142 ret, name = (self.data >> 8) & (self.data & 0xff), self.state.title()
144 if self.state == 'ADDRESS':
145 self.addr = self.data
146 if self.state == 'COMMAND':
149 self.ss_start = self.samplenum
152 self.putd(self.data >> 8)
154 self.putx([12, ['%s error: 0x%04X' % (name, self.data)]])
155 self.data = self.count = 0
156 self.ss_bit = self.ss_start = self.samplenum
160 if not self.samplerate:
161 raise SamplerateError('Cannot decode without samplerate.')
164 if self.options['cd_freq']:
165 cd_count = int(self.samplerate / self.options['cd_freq']) + 1
168 self.active = 0 if self.options['polarity'] == 'active-low' else 1
171 # Detect changes in the presence of an active input signal.
172 # The decoder can either be fed an already filtered RX signal
173 # or optionally can detect the presence of a carrier. Periods
174 # of inactivity (signal changes slower than the carrier freq,
175 # if specified) pass on the most recently sampled level. This
176 # approach works for filtered and unfiltered input alike, and
177 # only slightly extends the active phase of input signals with
178 # carriers included by one period of the carrier frequency.
179 # IR based communication protocols can cope with this slight
180 # inaccuracy just fine by design. Enabling carrier detection
181 # on already filtered signals will keep the length of their
182 # active period, but will shift their signal changes by one
183 # carrier period before they get passed to decoding logic.
185 (cur_ir,) = self.wait([{0: 'e'}, {'skip': cd_count}])
188 if cur_ir == prev_ir:
193 (self.ir,) = self.wait({0: 'e'})
195 if self.ir != self.active:
196 # Save the non-active edge, then wait for the next edge.
197 self.ss_other_edge = self.samplenum
200 b = self.samplenum - self.ss_bit
203 if self.state == 'IDLE':
204 if self.compare_with_tolerance(b, self.lc):
205 self.putpause('Long')
206 self.putx([5, ['Leader code', 'Leader', 'LC', 'L']])
207 self.ss_remote = self.ss_start
208 self.data = self.count = 0
209 self.state = 'ADDRESS'
210 elif self.compare_with_tolerance(b, self.rc):
211 self.putpause('Short')
212 self.putstop(self.samplenum)
213 self.samplenum += self.stop
214 self.putx([10, ['Repeat code', 'Repeat', 'RC', 'R']])
215 self.data = self.count = 0
216 self.ss_bit = self.ss_start = self.samplenum
217 elif self.state == 'ADDRESS':
220 self.state = 'ADDRESS#' if self.data_ok() else 'IDLE'
221 elif self.state == 'ADDRESS#':
224 self.state = 'COMMAND' if self.data_ok() else 'IDLE'
225 elif self.state == 'COMMAND':
228 self.state = 'COMMAND#' if self.data_ok() else 'IDLE'
229 elif self.state == 'COMMAND#':
232 self.state = 'STOP' if self.data_ok() else 'IDLE'
233 elif self.state == 'STOP':
234 self.putstop(self.ss_bit)
236 self.ss_bit = self.ss_start = self.samplenum