X-Git-Url: https://sigrok.org/gitweb/?a=blobdiff_plain;f=decoders%2Fi2s%2Fi2s.py;h=b921011589bd3592824efb6d68ff5ad9b3b76561;hb=0afa64aefc96649c74770dbcbbcfb5934d99fe18;hp=30497b3190d0e02f26ba906a713729019e4cd439;hpb=2ab416c214e248be8ece49bab2cabf2b28954cca;p=libsigrokdecode.git

diff --git a/decoders/i2s/i2s.py b/decoders/i2s/i2s.py
index 30497b3..b921011 100644
--- a/decoders/i2s/i2s.py
+++ b/decoders/i2s/i2s.py
@@ -30,18 +30,19 @@ class Decoder(srd.Decoder):
     id = 'i2s'
     name = 'I2S'
     longname = 'Integrated Interchip Sound'
-    desc = 'I2S is an electrical serial bus interface standard used ' \
-        'for connecting digital audio devices together.'
+    desc = 'Serial bus for connecting digital audio devices.'
     license = 'gplv2+'
     inputs = ['logic']
     outputs = ['i2s']
     probes = [
         {'id': 'sck', 'name': 'SCK', 'desc': 'Bit clock line'},
         {'id': 'ws', 'name': 'WS', 'desc': 'Word select line'},
-        {'id': 'sd', 'name': 'SD', 'desc': 'Serial Data line'},
+        {'id': 'sd', 'name': 'SD', 'desc': 'Serial data line'},
     ]
+    optional_probes = []
+    options = {}
     annotations = [
-        ['ASCII', 'Annotations in ASCII format'],
+        ['Hex', 'Annotations in hex format'],
     ]
 
     def __init__(self, **kwargs):
@@ -50,15 +51,29 @@ class Decoder(srd.Decoder):
         self.bitcount = 0
         self.data = 0
         self.samplesreceived = 0
+        self.first_sample = None
         self.start_sample = None
         self.samplenum = -1
+        self.wordlength = -1
 
     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 report(self):
-        return 'I2S: %d samples received' % self.samplesreceived
+
+        # Calculate the sample rate.
+        samplerate = '?'
+        if self.start_sample != None and \
+            self.first_sample != None and \
+            self.start_sample > self.first_sample:
+            samplerate = '%d' % (self.samplesreceived *
+                self.samplerate / (self.start_sample -
+                self.first_sample))
+
+        return 'I2S: %d %d-bit samples received at %sHz' % \
+            (self.samplesreceived, self.wordlength, samplerate)
 
     def decode(self, ss, es, data):
         for samplenum, (sck, ws, sd) in data:
@@ -68,29 +83,42 @@ class Decoder(srd.Decoder):
                 continue
 
             self.oldsck = sck
-            if sck == 0:   # Ignore the falling clock edge
+            if sck == 0:   # Ignore the falling clock edge.
                 continue
 
             self.data = (self.data << 1) | sd
             self.bitcount += 1
 
-            # This was not the LSB unless WS has flipped
+            # This was not the LSB unless WS has flipped.
             if ws == self.oldws:
                 continue
 
-            # Only submit the sample, if we received the beginning of it
+            # Only submit the sample, if we received the beginning of it.
             if self.start_sample != None:
                 self.samplesreceived += 1
                 self.put(self.start_sample, self.samplenum, self.out_proto,
-                    ['data', self.data])
+                         ['data', self.data])
                 self.put(self.start_sample, self.samplenum, self.out_ann,
-                    [ANN_HEX, ['%s %d-bits: 0x%08x' % ('L' if self.oldws else 'R',
-                    self.bitcount, self.data)]])
+                         [ANN_HEX, ['%s: 0x%08x' % ('L' if self.oldws else 'R',
+                         self.data)]])
+
+                # Check that the data word was the correct length.
+                if self.wordlength != -1 and self.wordlength != self.bitcount:
+                    self.put(self.start_sample, self.samplenum, self.out_ann,
+                        [ANN_HEX, ['WARNING: Received a %d-bit word, when a '
+                        '%d-bit word was expected' % (self.bitcount,
+                        self.wordlength)]])
+
+                self.wordlength = self.bitcount
 
             # Reset decoder state.
             self.data = 0
             self.bitcount = 0
             self.start_sample = self.samplenum
-                
+
+            # Save the first sample position.
+            if self.first_sample == None:
+                self.first_sample = self.samplenum
+
             self.oldws = ws
-            
\ No newline at end of file
+