2 ## This file is part of the libsigrokdecode project.
4 ## Copyright (C) 2015 Jeremy Swanson <jeremy@rakocontrols.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
22 class SamplerateError(Exception):
25 class Decoder(srd.Decoder):
29 longname = 'Digital Serial Interface'
30 desc = 'DSI lighting control protocol.'
35 {'id': 'dsi', 'name': 'DSI', 'desc': 'DSI data line'},
38 {'id': 'polarity', 'desc': 'Polarity', 'default': 'active-high',
39 'values': ('active-low', 'active-high')},
43 ('startbit', 'Start bit'),
44 ('level', 'Dimmer level'),
48 ('bits', 'Bits', (0,)),
49 ('raw', 'Raw data', (3,)),
50 ('fields', 'Fields', (1, 2)),
54 self.samplerate = None
56 self.edges, self.bits, self.ss_es_bits = [], [], []
60 self.out_ann = self.register(srd.OUTPUT_ANN)
61 self.old_dsi = 1 if self.options['polarity'] == 'active-low' else 0
63 def metadata(self, key, value):
64 if key == srd.SRD_CONF_SAMPLERATE:
65 self.samplerate = value
66 # One bit: 1666.7us (one half low, one half high).
67 # This is how many samples are in 1TE.
68 self.halfbit = int((self.samplerate * 0.0016667) / 2.0)
70 def putb(self, bit1, bit2, data):
71 ss, es = self.ss_es_bits[bit1][0], self.ss_es_bits[bit2][1]
72 self.put(ss, es, self.out_ann, data)
74 def handle_bits(self, length):
75 a, c, f, g, b = 0, 0, 0, 0, self.bits
76 # Individual raw bits.
77 for i in range(length):
79 ss = max(0, self.bits[0][0])
81 ss = self.ss_es_bits[i - 1][1]
82 es = self.bits[i][0] + (self.halfbit * 2)
83 self.ss_es_bits.append([ss, es])
84 self.putb(i, i, [0, ['%d' % self.bits[i][1]]])
86 s = ['Startbit: %d' % b[0][1], 'ST: %d' % b[0][1], 'ST', 'S', 'S']
87 self.putb(0, 0, [1, s])
88 self.putb(0, 0, [3, s])
91 f |= (b[1 + i][1] << (7 - i))
93 if length == 9: # BACKWARD Frame
94 s = ['Data: %02X' % f, 'Dat: %02X' % f,
95 'Dat: %02X' % f, 'D: %02X' % f, 'D']
96 self.putb(1, 8, [3, s])
97 s = ['Level: %d%%' % g, 'Lev: %d%%' % g,
98 'Lev: %d%%' % g, 'L: %d' % g, 'D']
99 self.putb(1, 8, [2, s])
102 def reset_decoder_state(self):
103 self.edges, self.bits, self.ss_es_bits = [], [], []
107 if not self.samplerate:
108 raise SamplerateError('Cannot decode without samplerate.')
111 (self.dsi,) = self.wait()
112 if self.options['polarity'] == 'active-high':
113 self.dsi ^= 1 # Invert.
116 if self.state == 'IDLE':
117 # Wait for any edge (rising or falling).
118 if self.old_dsi == self.dsi:
120 # Add in the first half of the start bit.
121 self.edges.append(self.samplenum - int(self.halfbit))
122 self.edges.append(self.samplenum)
124 self.phase0 = self.dsi ^ 1
125 self.state = 'PHASE1'
126 self.old_dsi = self.dsi
127 # Get the next sample point.
128 self.old_dsi = self.dsi
131 if self.old_dsi != self.dsi:
132 self.edges.append(self.samplenum)
133 elif self.samplenum == (self.edges[-1] + int(self.halfbit * 1.5)):
134 self.edges.append(self.samplenum - int(self.halfbit * 0.5))
139 if self.state == 'PHASE0':
141 self.state = 'PHASE1'
142 elif self.state == 'PHASE1':
143 if (bit == 1) and (self.phase0 == 1): # Stop bit.
144 if len(self.bits) == 17 or len(self.bits) == 9:
145 # Forward or Backward.
146 self.handle_bits(len(self.bits))
147 self.reset_decoder_state() # Reset upon errors.
150 self.bits.append([self.edges[-3], bit])
151 self.state = 'PHASE0'
153 self.old_dsi = self.dsi