X-Git-Url: https://sigrok.org/gitweb/?p=libsigrokdecode.git;a=blobdiff_plain;f=decoders%2Fi2s%2Fpd.py;h=b0b177f1f007f0687e460db06e49361121af18a3;hp=b1f36caba7d927925dfcfbd4e7809c10bc6f6932;hb=4539e9ca58966ce3c9cad4801b16c315e86ace01;hpb=2b2b7c300e6771ac6aa2982ced109ef3f02f3636 diff --git a/decoders/i2s/pd.py b/decoders/i2s/pd.py index b1f36ca..b0b177f 100644 --- a/decoders/i2s/pd.py +++ b/decoders/i2s/pd.py @@ -14,81 +14,126 @@ ## 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 . ## -# I2S protocol decoder - import sigrokdecode as srd +''' +OUTPUT_PYTHON format: + +Packet: +[, ] + +, : + - 'DATA', [, ] + +: 'L' or 'R' +: integer +''' + +class SamplerateError(Exception): + pass + class Decoder(srd.Decoder): - api_version = 1 + api_version = 3 id = 'i2s' - name = 'I2S' + name = 'I²S' longname = 'Integrated Interchip Sound' desc = 'Serial bus for connecting digital audio devices.' license = 'gplv2+' inputs = ['logic'] outputs = ['i2s'] - probes = [ + channels = ( {'id': 'sck', 'name': 'SCK', 'desc': 'Bit clock line'}, {'id': 'ws', 'name': 'WS', 'desc': 'Word select line'}, {'id': 'sd', 'name': 'SD', 'desc': 'Serial data line'}, - ] - optional_probes = [] - options = {} - annotations = [ - ['left', 'Left channel'], - ['right', 'Right channel'], - ['warnings', 'Warnings'], - ] - - def __init__(self, **kwargs): - self.oldsck = 1 + ) + annotations = ( + ('left', 'Left channel'), + ('right', 'Right channel'), + ('warnings', 'Warnings'), + ) + binary = ( + ('wav', 'WAV file'), + ) + + def __init__(self): + self.samplerate = None self.oldws = 1 self.bitcount = 0 self.data = 0 self.samplesreceived = 0 self.first_sample = None - self.start_sample = None + self.ss_block = None self.wordlength = -1 + self.wrote_wav_header = False - def start(self, metadata): - self.samplerate = metadata['samplerate'] - self.out_proto = self.add(srd.OUTPUT_PROTO, 'i2s') - self.out_ann = self.add(srd.OUTPUT_ANN, 'i2s') + def start(self): + self.out_python = self.register(srd.OUTPUT_PYTHON) + self.out_binary = self.register(srd.OUTPUT_BINARY) + self.out_ann = self.register(srd.OUTPUT_ANN) + + def metadata(self, key, value): + if key == srd.SRD_CONF_SAMPLERATE: + self.samplerate = value def putpb(self, data): - self.put(self.start_sample, self.samplenum, self.out_proto, data) + self.put(self.ss_block, self.samplenum, self.out_python, data) + + def putbin(self, data): + self.put(self.ss_block, self.samplenum, self.out_binary, data) def putb(self, data): - self.put(self.start_sample, self.samplenum, self.out_ann, data) + self.put(self.ss_block, self.samplenum, self.out_ann, data) def report(self): # Calculate the sample rate. samplerate = '?' - if self.start_sample != None and \ - self.first_sample != None and \ - self.start_sample > self.first_sample: + if self.ss_block is not None and \ + self.first_sample is not None and \ + self.ss_block > self.first_sample: samplerate = '%d' % (self.samplesreceived * - self.samplerate / (self.start_sample - + self.samplerate / (self.ss_block - self.first_sample)) - return 'I2S: %d %d-bit samples received at %sHz' % \ + return 'I²S: %d %d-bit samples received at %sHz' % \ (self.samplesreceived, self.wordlength, samplerate) - def decode(self, ss, es, data): - for self.samplenum, (sck, ws, sd) in data: - - # Ignore sample if the bit clock hasn't changed. - if sck == self.oldsck: - continue - - self.oldsck = sck - if sck == 0: # Ignore the falling clock edge. - continue + def wav_header(self): + # Chunk descriptor + h = b'RIFF' + h += b'\x24\x80\x00\x00' # Chunk size (2084) + h += b'WAVE' + # Fmt subchunk + h += b'fmt ' + h += b'\x10\x00\x00\x00' # Subchunk size (16 bytes) + h += b'\x01\x00' # Audio format (0x0001 == PCM) + h += b'\x02\x00' # Number of channels (2) + h += b'\x80\x3e\x00\x00' # Samplerate (16000) + h += b'\x00\x7d\x00\x00' # Byterate (32000) + h += b'\x04\x00' # Blockalign (4) + h += b'\x10\x00' # Bits per sample (16) + # Data subchunk + h += b'data' + h += b'\xff\xff\x00\x00' # Subchunk size (65535 bytes) TODO + return h + + def wav_sample(self, sample): + # TODO: This currently assumes U32 samples, and converts to S16. + s = sample >> 16 + if s >= 0x8000: + s -= 0x10000 + lo, hi = s & 0xff, (s >> 8) & 0xff + return bytes([lo, hi]) + + def decode(self): + if not self.samplerate: + raise SamplerateError('Cannot decode without samplerate.') + while True: + # Wait for a rising edge on the SCK pin. + sck, ws, sd = self.wait({0: 'r'}) self.data = (self.data << 1) | sd self.bitcount += 1 @@ -98,10 +143,23 @@ class Decoder(srd.Decoder): continue # Only submit the sample, if we received the beginning of it. - if self.start_sample != None: + if self.ss_block is not None: + + if not self.wrote_wav_header: + self.put(0, 0, self.out_binary, [0, self.wav_header()]) + self.wrote_wav_header = True + self.samplesreceived += 1 - self.putpb(['data', self.data]) - self.putb([0 if self.oldws else 1, ['0x%08x' % self.data]]) + + idx = 0 if self.oldws else 1 + c1 = 'Left channel' if self.oldws else 'Right channel' + c2 = 'Left' if self.oldws else 'Right' + c3 = 'L' if self.oldws else 'R' + v = '%08x' % self.data + self.putpb(['DATA', [c3, self.data]]) + self.putb([idx, ['%s: %s' % (c1, v), '%s: %s' % (c2, v), + '%s: %s' % (c3, v), c3]]) + self.putbin([0, self.wav_sample(self.data)]) # Check that the data word was the correct length. if self.wordlength != -1 and self.wordlength != self.bitcount: @@ -113,11 +171,10 @@ class Decoder(srd.Decoder): # Reset decoder state. self.data = 0 self.bitcount = 0 - self.start_sample = self.samplenum + self.ss_block = self.samplenum # Save the first sample position. - if self.first_sample == None: + if self.first_sample is None: self.first_sample = self.samplenum self.oldws = ws -