spdif: Convert to PD API version 3.
authorUwe Hermann <uwe@hermann-uwe.de>
Fri, 26 Aug 2016 13:19:21 +0000 (15:19 +0200)
committerUwe Hermann <uwe@hermann-uwe.de>
Wed, 7 Dec 2016 21:45:47 +0000 (22:45 +0100)
decoders/spdif/pd.py

index da3ca283ca87e8761ed05288c1bfc7fae3d58382..e22f654a906f519135867881cfbca2e2a19b5d81 100644 (file)
@@ -24,7 +24,7 @@ class SamplerateError(Exception):
     pass
 
 class Decoder(srd.Decoder):
-    api_version = 2
+    api_version = 3
     id = 'spdif'
     name = 'S/PDIF'
     longname = 'Sony/Philips Digital Interface Format'
@@ -60,9 +60,9 @@ class Decoder(srd.Decoder):
 
     def __init__(self):
         self.state = 'GET FIRST PULSE WIDTH'
-        self.olddata = None
         self.ss_edge = None
         self.first_edge = True
+        self.samplenum_prev_edge = 0
         self.pulse_width = 0
 
         self.clocks = []
@@ -80,6 +80,9 @@ class Decoder(srd.Decoder):
     def start(self):
         self.out_ann = self.register(srd.OUTPUT_ANN)
 
+        # Assume that the initial pin state is logic 0.
+        self.initial_pins = [0]
+
     def metadata(self, key, value):
         if key == srd.SRD_CONF_SAMPLERATE:
             self.samplerate = value
@@ -218,40 +221,26 @@ class Decoder(srd.Decoder):
 
         self.last_preamble = self.samplenum
 
-    def decode(self, ss, es, data):
+    def decode(self):
         if not self.samplerate:
             raise SamplerateError('Cannot decode without samplerate.')
 
-        for (self.samplenum, pins) in data:
-            data = pins[0]
-
-            # Initialize self.olddata with the first sample value.
-            if self.olddata is None:
-                self.olddata = data
-                continue
-
-            # First we need to recover the clock.
-            if self.olddata == data:
-                self.pulse_width += 1
-                continue
-
-            # 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 == '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()
-
-            self.pulse_width = 0
-
-            self.olddata = data
+        # 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()