## 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
+## along with this program; if not, see <http://www.gnu.org/licenses/>.
##
import sigrokdecode as srd
pass
class Decoder(srd.Decoder):
- api_version = 2
+ api_version = 3
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']
+ outputs = []
+ tags = ['Audio', 'PC']
channels = (
{'id': 'data', 'name': 'Data', 'desc': 'Data line'},
)
('parity', 'Parity Bit'),
)
annotation_rows = (
- ('info', 'Info', (0, 1, 3, 5, 6, 7, 8)),
('bits', 'Bits', (2,)),
+ ('info', 'Info', (0, 1, 3, 5, 6, 7, 8)),
('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
+ def puty(self, data):
+ self.put(self.ss_edge, self.samplenum, self.out_ann, data)
+
+ def __init__(self):
+ self.reset()
+
+ def reset(self):
+ self.state = 'GET FIRST PULSE WIDTH'
self.ss_edge = None
self.first_edge = True
+ self.samplenum_prev_edge = 0
self.pulse_width = 0
self.clocks = []
if key == srd.SRD_CONF_SAMPLERATE:
self.samplerate = value
- def get_pulse_type(self, pulse):
+ def get_pulse_type(self):
if self.range1 == 0 or self.range2 == 0:
return -1
- if pulse >= self.range2:
+ if self.pulse_width >= self.range2:
return 2
- elif pulse >= self.range1:
+ elif self.pulse_width >= 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]
+ 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', 'Unknown Prea.', 'U']])
+ self.preamble = []
+ self.seen_preamble = True
+ self.bitcount = 0
+ self.first_one = True
- # Initialize first self.olddata with the first sample value.
- if self.olddata == None:
- self.olddata = data
- continue
+ self.last_preamble = self.samplenum
- # 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
+ def decode(self):
+ if not self.samplerate:
+ raise SamplerateError('Cannot decode without samplerate.')
+ # Throw away first detected edge as it might be mangled data.
+ self.wait({0: 'e'})
+
+ while True:
+ # Wait for any edge (rising or falling).
+ (data,) = self.wait({0: 'e'})
+ self.pulse_width = self.samplenum - self.samplenum_prev_edge - 1
+ self.samplenum_prev_edge = self.samplenum
+
+ if self.state == 'GET FIRST PULSE WIDTH':
+ self.find_first_pulse_width()
+ elif self.state == 'GET SECOND PULSE WIDTH':
+ self.find_second_pulse_width()
+ elif self.state == 'GET THIRD PULSE WIDTH':
+ self.find_third_pulse_width()
+ elif self.state == 'DECODE STREAM':
+ self.decode_stream()
+ elif self.state == 'DECODE PREAMBLE':
+ self.decode_preamble()