+ def find_first_pulse_width(self):
+ if self.pulse_width != 0:
+ self.clocks.append(self.pulse_width)
+ self.state = 'GET SECOND PULSE WIDTH'
+
+ def find_second_pulse_width(self):
+ 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 = 'GET THIRD PULSE WIDTH'
+
+ def find_third_pulse_width(self):
+ if not ((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))):
+ return
+
+ 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.puty([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 = 'DECODE STREAM'
+
+ def decode_stream(self):
+ pulse = self.get_pulse_type()
+
+ if not self.seen_preamble:
+ # This is probably the start of a preamble, decode it.
+ if pulse == 2:
+ self.preamble.append(self.get_pulse_type())
+ self.state = 'DECODE PREAMBLE'
+ self.ss_edge = self.samplenum - self.pulse_width - 1
+ return
+
+ # We've seen a 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
+
+ def decode_preamble(self):
+ if self.preamble_state == 0:
+ self.preamble.append(self.get_pulse_type())
+ self.preamble_state = 1
+ elif self.preamble_state == 1:
+ self.preamble.append(self.get_pulse_type())
+ self.preamble_state = 2
+ elif self.preamble_state == 2:
+ self.preamble.append(self.get_pulse_type())
+ self.preamble_state = 0
+ self.state = 'DECODE STREAM'
+ if self.preamble == [2, 0, 1, 0]:
+ self.puty([1, ['Preamble W', 'W']])
+ elif self.preamble == [2, 2, 1, 1]:
+ self.puty([1, ['Preamble M', 'M']])
+ elif self.preamble == [2, 1, 1, 2]:
+ self.puty([1, ['Preamble B', 'B']])
+ else:
+ self.puty([1, ['Unknown Preamble', 'Unkown Prea.', 'U']])
+ self.preamble = []
+ self.seen_preamble = True
+ self.bitcount = 0
+ self.first_one = True
+
+ self.last_preamble = self.samplenum
+