[libsigrokdecode.git] / decoders / spdif / pd.py

##
## This file is part of the libsigrokdecode project.
##
## Copyright (C) 2014 Guenther Wenninger <robin@bitschubbser.org>
##
## 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, or
## (at your option) any later version.
##
## 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 St, Fifth Floor, Boston, MA  02110-1301 USA
##

import sigrokdecode as srd

class SamplerateError(Exception):
    pass

class Decoder(srd.Decoder):
    api_version = 2
    id = 'spdif'
    name = 'S/PDIF'
    longname = 'Sony/Philips Digital Interface Format'
    desc = 'Serial bus for connecting digital audio devices.'
    license = 'gplv2+'
    inputs = ['logic']
    outputs = ['spdif']
    channels = (
        {'id': 'data', 'name': 'Data', 'desc': 'Data line'},
    )
    annotations = (
        ('bitrate', 'Bitrate / baudrate'),
        ('preamble', 'Preamble'),
        ('bits', 'Bits'),
        ('aux', 'Auxillary-audio-databits'),
        ('samples', 'Audio Samples'),
        ('validity', 'Data Valid'),
        ('subcode', 'Subcode data'),
        ('chan_stat', 'Channnel Status'),
        ('parity', 'Parity Bit'),
    )
    annotation_rows = (
        ('info', 'Info', (0, 1, 3, 5, 6, 7, 8)),
        ('bits', 'Bits', (2,)),
        ('samples', 'Samples', (4,)),
    )

    def putx(self, ss, es, data):
        self.put(ss, es, self.out_ann, data)

    def __init__(self, **kwargs):
        self.state  = 0
        self.olddata = None
        self.ss_edge = None
        self.first_edge = True
        self.pulse_width = 0

        self.clocks = []
        self.range1 = 0
        self.range2 = 0

        self.preamble_state = 0
        self.preamble = []
        self.seen_preamble = False
        self.last_preamble = 0

        self.first_one = True
        self.subframe = []

    def start(self):
        self.out_ann = self.register(srd.OUTPUT_ANN)

    def metadata(self, key, value):
        if key == srd.SRD_CONF_SAMPLERATE:
            self.samplerate = value

    def get_pulse_type(self, pulse):
        if self.range1 == 0 or self.range2 == 0:
            return -1
        if pulse >= self.range2:
            return 2
        elif pulse >= self.range1:
            return 0
        else:
            return 1

    def decode(self, ss, es, data):
        if not self.samplerate:
            raise SamplerateError('Cannot decode without samplerate.')

        for (self.samplenum, pins) in data:
            data = pins[0]

            # Initialize first self.olddata with the first sample value.
            if self.olddata == None:
                self.olddata = data
                continue

            # First we need to recover the clock.
            if self.olddata == data:
                self.pulse_width += 1
            else:
                # Found rising or falling edge.
                if self.first_edge:
                    # Throw away first detected edge as it might be mangled data.
                    self.first_edge = False
                    self.pulse_width = 0
                else:
                    if self.state == 0:
                        # Find first pulse width.
                        if self.pulse_width != 0:
                            self.clocks.append(self.pulse_width)
                            self.state = 1

                    elif self.state == 1:
                        # Find second pulse width.
                        if self.pulse_width > (self.clocks[0] * 1.3) or self.pulse_width < (self.clocks[0] * 0.7):
                            self.clocks.append(self.pulse_width)
                            self.state = 2

                    elif self.state == 2:
                        # Find third pulse width.
                        if (self.pulse_width > (self.clocks[0] * 1.3) or self.pulse_width < (self.clocks[0] * 0.7)) \
                                and (self.pulse_width > (self.clocks[1] * 1.3) or self.pulse_width < (self.clocks[1] * 0.7)):
                            self.clocks.append(self.pulse_width)
                            self.clocks.sort()
                            self.range1 = (self.clocks[0] + self.clocks[1]) / 2
                            self.range2 = (self.clocks[1] + self.clocks[2]) / 2
                            spdif_bitrate = int(self.samplerate / (self.clocks[2] / 1.5))
                            self.ss_edge = 0

                            self.putx(self.ss_edge, self.samplenum, [0, \
                                    ['Signal Bitrate: %d Mbit/s (=> %d kHz)' % \
                                    (spdif_bitrate, (spdif_bitrate/ (2 * 32)))]])

                            clock_period_nsec = 1000000000 / spdif_bitrate

                            self.last_preamble = self.samplenum
                            # We are done recovering the clock, now let's decode the data stream.
                            self.state = 3

                    elif self.state == 3:
                        # Decode the stream.
                        pulse = self.get_pulse_type(self.pulse_width)

                        if self.seen_preamble:
                            if pulse == 1 and self.first_one:
                                self.first_one = False
                                self.subframe.append([pulse, self.samplenum - self.pulse_width - 1, self.samplenum])
                            elif pulse == 1 and not self.first_one:
                                self.subframe[-1][2] = self.samplenum
                                self.putx(self.subframe[-1][1], self.samplenum, [2, ['1']])
                                self.bitcount += 1
                                self.first_one = True
                            else:
                                self.subframe.append([pulse, self.samplenum - self.pulse_width - 1, self.samplenum])
                                self.putx(self.samplenum - self.pulse_width - 1, self.samplenum, [2, ['0']])
                                self.bitcount += 1

                            if self.bitcount == 28:
                                aux_audio_data = self.subframe[0:4]
                                sam, sam_rot = '', ''
                                for a in aux_audio_data:
                                    sam = sam + str(a[0])
                                    sam_rot = str(a[0]) + sam_rot
                                sample = self.subframe[4:24]
                                for s in sample:
                                    sam = sam + str(s[0])
                                    sam_rot = str(s[0]) + sam_rot
                                validity = self.subframe[24:25]
                                subcode_data = self.subframe[25:26]
                                channel_status = self.subframe[26:27]
                                parity = self.subframe[27:28]

                                self.putx(aux_audio_data[0][1], aux_audio_data[3][2], \
                                          [3, ['Aux 0x%x' % int(sam, 2), '0x%x' % int(sam, 2)]])
                                self.putx(sample[0][1], sample[19][2], \
                                          [3, ['Sample 0x%x' % int(sam, 2), '0x%x' % int(sam, 2)]])
                                self.putx(aux_audio_data[0][1], sample[19][2], \
                                          [4, ['Audio 0x%x' % int(sam_rot, 2), '0x%x' % int(sam_rot, 2)]])
                                if validity[0][0] == 0:
                                    self.putx(validity[0][1], validity[0][2], [5, ['V']])
                                else:
                                    self.putx(validity[0][1], validity[0][2], [5, ['E']])
                                self.putx(subcode_data[0][1], subcode_data[0][2], [6, ['S: %d' % subcode_data[0][0]]])
                                self.putx(channel_status[0][1], channel_status[0][2], [7, ['C: %d' % channel_status[0][0]]])
                                self.putx(parity[0][1], parity[0][2], [8, ['P: %d' % parity[0][0]]])

                                self.subframe = []
                                self.seen_preamble = False
                                self.bitcount = 0
                        else:
                            # This is probably the start of a preamble, so go
                            # ahead and decode it.
                            if pulse == 2:
                                self.preamble.append(self.get_pulse_type(self.pulse_width))
                                self.state = 4 # Decode a preamble.
                                self.ss_edge = self.samplenum - self.pulse_width - 1

                    elif self.state == 4:
                        if self.preamble_state == 0:
                            self.preamble.append(self.get_pulse_type(self.pulse_width))
                            self.preamble_state = 1
                        elif self.preamble_state == 1:
                            self.preamble.append(self.get_pulse_type(self.pulse_width))
                            self.preamble_state = 2
                        elif self.preamble_state == 2:
                            self.preamble.append(self.get_pulse_type(self.pulse_width))
                            self.preamble_state = 0
                            self.state = 3
                            if self.preamble == [2, 0, 1, 0]:
                                self.putx(self.ss_edge, self.samplenum, [1, ['Preamble W', 'W']])
                            elif self.preamble == [2, 2, 1, 1]:
                                self.putx(self.ss_edge, self.samplenum, [1, ['Preamble M', 'M']])
                            elif self.preamble == [2, 1, 1, 2]:
                                self.putx(self.ss_edge, self.samplenum, [1, ['Preamble B', 'B']])
                            else:
                                self.putx(self.ss_edge, self.samplenum, [1, ['Unknown Preamble', 'Unkown Prea.', 'U']])
                            self.preamble = []
                            self.seen_preamble = True
                            self.bitcount = 0
                            self.first_one = True

                        self.last_preamble = self.samplenum

                self.pulse_width = 0

            self.olddata = data
Commit	Line	Data
cb6d4c6d GW	1	##
	2	## This file is part of the libsigrokdecode project.
	3	##
	4	## Copyright (C) 2014 Guenther Wenninger <robin@bitschubbser.org>
	5	##
	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.
	10	##
	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.
	15	##
	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
	19	##
	20
	21	import sigrokdecode as srd
	22
	23	class SamplerateError(Exception):
	24	pass
	25
	26	class Decoder(srd.Decoder):
	27	api_version = 2
	28	id = 'spdif'
	29	name = 'S/PDIF'
	30	longname = 'Sony/Philips Digital Interface Format'
	31	desc = 'Serial bus for connecting digital audio devices.'
	32	license = 'gplv2+'
	33	inputs = ['logic']
	34	outputs = ['spdif']
	35	channels = (
	36	{'id': 'data', 'name': 'Data', 'desc': 'Data line'},
	37	)
	38	annotations = (
	39	('bitrate', 'Bitrate / baudrate'),
	40	('preamble', 'Preamble'),
	41	('bits', 'Bits'),
	42	('aux', 'Auxillary-audio-databits'),
	43	('samples', 'Audio Samples'),
	44	('validity', 'Data Valid'),
	45	('subcode', 'Subcode data'),
	46	('chan_stat', 'Channnel Status'),
	47	('parity', 'Parity Bit'),
	48	)
	49	annotation_rows = (
	50	('info', 'Info', (0, 1, 3, 5, 6, 7, 8)),
	51	('bits', 'Bits', (2,)),
	52	('samples', 'Samples', (4,)),
	53	)
	54
	55	def putx(self, ss, es, data):
	56	self.put(ss, es, self.out_ann, data)
	57
	58	def __init__(self, **kwargs):
	59	self.state = 0
	60	self.olddata = None
	61	self.ss_edge = None
	62	self.first_edge = True
	63	self.pulse_width = 0
	64
65	self.clocks = []
66	self.range1 = 0
67	self.range2 = 0
68
69	self.preamble_state = 0
70	self.preamble = []
71	self.seen_preamble = False
72	self.last_preamble = 0
73
74	self.first_one = True
75	self.subframe = []
76
77	def start(self):
78	self.out_ann = self.register(srd.OUTPUT_ANN)
79
80	def metadata(self, key, value):
81	if key == srd.SRD_CONF_SAMPLERATE:
82	self.samplerate = value
83
84	def get_pulse_type(self, pulse):
85	if self.range1 == 0 or self.range2 == 0:
86	return -1
87	if pulse >= self.range2:
88	return 2
89	elif pulse >= self.range1:
90	return 0
91	else:
92	return 1
93
94	def decode(self, ss, es, data):
95	if not self.samplerate:
96	raise SamplerateError('Cannot decode without samplerate.')
97
98	for (self.samplenum, pins) in data:
99	data = pins[0]
100
101	# Initialize first self.olddata with the first sample value.
102	if self.olddata == None:
103	self.olddata = data
104	continue
105
106	# First we need to recover the clock.
107	if self.olddata == data:
108	self.pulse_width += 1
109	else:
110	# Found rising or falling edge.
111	if self.first_edge:
112	# Throw away first detected edge as it might be mangled data.
113	self.first_edge = False
114	self.pulse_width = 0
115	else:
116	if self.state == 0:
117	# Find first pulse width.
118	if self.pulse_width != 0:
119	self.clocks.append(self.pulse_width)
120	self.state = 1
121
122	elif self.state == 1:
123	# Find second pulse width.
124	if self.pulse_width > (self.clocks[0] * 1.3) or self.pulse_width < (self.clocks[0] * 0.7):
125	self.clocks.append(self.pulse_width)
126	self.state = 2
127
128	elif self.state == 2:
129	# Find third pulse width.
130	if (self.pulse_width > (self.clocks[0] * 1.3) or self.pulse_width < (self.clocks[0] * 0.7)) \
131	and (self.pulse_width > (self.clocks[1] * 1.3) or self.pulse_width < (self.clocks[1] * 0.7)):
132	self.clocks.append(self.pulse_width)
133	self.clocks.sort()
134	self.range1 = (self.clocks[0] + self.clocks[1]) / 2
135	self.range2 = (self.clocks[1] + self.clocks[2]) / 2
136	spdif_bitrate = int(self.samplerate / (self.clocks[2] / 1.5))
137	self.ss_edge = 0
138
139	self.putx(self.ss_edge, self.samplenum, [0, \
140	['Signal Bitrate: %d Mbit/s (=> %d kHz)' % \
141	(spdif_bitrate, (spdif_bitrate/ (2 * 32)))]])
142
143	clock_period_nsec = 1000000000 / spdif_bitrate
144
145	self.last_preamble = self.samplenum
146	# We are done recovering the clock, now let's decode the data stream.
147	self.state = 3
148
149	elif self.state == 3:
150	# Decode the stream.
151	pulse = self.get_pulse_type(self.pulse_width)
152
153	if self.seen_preamble:
154	if pulse == 1 and self.first_one:
155	self.first_one = False
156	self.subframe.append([pulse, self.samplenum - self.pulse_width - 1, self.samplenum])
157	elif pulse == 1 and not self.first_one:
158	self.subframe[-1][2] = self.samplenum
159	self.putx(self.subframe[-1][1], self.samplenum, [2, ['1']])
160	self.bitcount += 1
161	self.first_one = True
162	else:
163	self.subframe.append([pulse, self.samplenum - self.pulse_width - 1, self.samplenum])
164	self.putx(self.samplenum - self.pulse_width - 1, self.samplenum, [2, ['0']])
165	self.bitcount += 1
166
167	if self.bitcount == 28:
168	aux_audio_data = self.subframe[0:4]
169	sam, sam_rot = '', ''
170	for a in aux_audio_data:
171	sam = sam + str(a[0])
172	sam_rot = str(a[0]) + sam_rot
173	sample = self.subframe[4:24]
174	for s in sample:
175	sam = sam + str(s[0])
176	sam_rot = str(s[0]) + sam_rot
177	validity = self.subframe[24:25]
178	subcode_data = self.subframe[25:26]
179	channel_status = self.subframe[26:27]
180	parity = self.subframe[27:28]
181
182	self.putx(aux_audio_data[0][1], aux_audio_data[3][2], \
183	[3, ['Aux 0x%x' % int(sam, 2), '0x%x' % int(sam, 2)]])
184	self.putx(sample[0][1], sample[19][2], \
185	[3, ['Sample 0x%x' % int(sam, 2), '0x%x' % int(sam, 2)]])
186	self.putx(aux_audio_data[0][1], sample[19][2], \
187	[4, ['Audio 0x%x' % int(sam_rot, 2), '0x%x' % int(sam_rot, 2)]])
188	if validity[0][0] == 0:
189	self.putx(validity[0][1], validity[0][2], [5, ['V']])
190	else:
191	self.putx(validity[0][1], validity[0][2], [5, ['E']])
192	self.putx(subcode_data[0][1], subcode_data[0][2], [6, ['S: %d' % subcode_data[0][0]]])
193	self.putx(channel_status[0][1], channel_status[0][2], [7, ['C: %d' % channel_status[0][0]]])
194	self.putx(parity[0][1], parity[0][2], [8, ['P: %d' % parity[0][0]]])
195
196	self.subframe = []
197	self.seen_preamble = False
198	self.bitcount = 0
199	else:
200	# This is probably the start of a preamble, so go
201	# ahead and decode it.
202	if pulse == 2:
203	self.preamble.append(self.get_pulse_type(self.pulse_width))
204	self.state = 4 # Decode a preamble.
205	self.ss_edge = self.samplenum - self.pulse_width - 1
206
207	elif self.state == 4:
208	if self.preamble_state == 0:
209	self.preamble.append(self.get_pulse_type(self.pulse_width))
210	self.preamble_state = 1
211	elif self.preamble_state == 1:
212	self.preamble.append(self.get_pulse_type(self.pulse_width))
213	self.preamble_state = 2
214	elif self.preamble_state == 2:
215	self.preamble.append(self.get_pulse_type(self.pulse_width))
216	self.preamble_state = 0
217	self.state = 3
218	if self.preamble == [2, 0, 1, 0]:
219	self.putx(self.ss_edge, self.samplenum, [1, ['Preamble W', 'W']])
220	elif self.preamble == [2, 2, 1, 1]:
221	self.putx(self.ss_edge, self.samplenum, [1, ['Preamble M', 'M']])
222	elif self.preamble == [2, 1, 1, 2]:
223	self.putx(self.ss_edge, self.samplenum, [1, ['Preamble B', 'B']])
224	else:
225	self.putx(self.ss_edge, self.samplenum, [1, ['Unknown Preamble', 'Unkown Prea.', 'U']])
226	self.preamble = []
227	self.seen_preamble = True
228	self.bitcount = 0
229	self.first_one = True
230
231	self.last_preamble = self.samplenum
232
233	self.pulse_width = 0
234
235	self.olddata = data
236