onewire_link: Fix a bug when the samplerate is too low for the PD.

The code was trying to emit annotations before
self.register(srd.OUTPUT_ANN) was run.

This fixes bug #357.

1 files changed, 37 insertions, 33 deletions

diff --git a/decoders/onewire_link/pd.py b/decoders/onewire_link/pd.py
index 2d4e089..2be0242 100644
--- a/decoders/onewire_link/pd.py
+++ b/decoders/onewire_link/pd.py
@@ -109,11 +109,7 @@ class Decoder(srd.Decoder):
         self.out_python = self.register(srd.OUTPUT_PYTHON)
         self.out_ann = self.register(srd.OUTPUT_ANN)
 
-    def metadata(self, key, value):
-        if key != srd.SRD_CONF_SAMPLERATE:
-            return
-        self.samplerate = value
-
+    def checks(self):
         # Check if samplerate is appropriate.
         if self.options['overdrive'] == 'yes':
             if self.samplerate < 2000000:
@@ -126,37 +122,10 @@ class Decoder(srd.Decoder):
             if self.samplerate < 400000:
                 self.putm([1, ['Sampling rate is too low. Must be above ' +
                                '400kHz for proper normal mode decoding.']])
-            elif (self.samplerate < 1000000):
+            elif self.samplerate < 1000000:
                 self.putm([1, ['Sampling rate is suggested to be above ' +
                                '1MHz for proper normal mode decoding.']])
 
-        # The default 1-Wire time base is 30us. This is used to calculate
-        # sampling times.
-        samplerate = float(self.samplerate)
-
-        x = float(self.options['cnt_normal_bit']) / 1000000.0
-        self.cnt_normal_bit = int(samplerate * x) - 1
-        x = float(self.options['cnt_normal_slot']) / 1000000.0
-        self.cnt_normal_slot = int(samplerate * x) - 1
-        x = float(self.options['cnt_normal_presence']) / 1000000.0
-        self.cnt_normal_presence = int(samplerate * x) - 1
-        x = float(self.options['cnt_normal_reset']) / 1000000.0
-        self.cnt_normal_reset = int(samplerate * x) - 1
-        x = float(self.options['cnt_overdrive_bit']) / 1000000.0
-        self.cnt_overdrive_bit = int(samplerate * x) - 1
-        x = float(self.options['cnt_overdrive_slot']) / 1000000.0
-        self.cnt_overdrive_slot = int(samplerate * x) - 1
-        x = float(self.options['cnt_overdrive_presence']) / 1000000.0
-        self.cnt_overdrive_presence = int(samplerate * x) - 1
-        x = float(self.options['cnt_overdrive_reset']) / 1000000.0
-        self.cnt_overdrive_reset = int(samplerate * x) - 1
-
-        # Organize values into lists.
-        self.cnt_bit = [self.cnt_normal_bit, self.cnt_overdrive_bit]
-        self.cnt_presence = [self.cnt_normal_presence, self.cnt_overdrive_presence]
-        self.cnt_reset = [self.cnt_normal_reset, self.cnt_overdrive_reset]
-        self.cnt_slot = [self.cnt_normal_slot, self.cnt_overdrive_slot]
-
         # Check if sample times are in the allowed range.
 
         time_min = float(self.cnt_normal_bit) / self.samplerate
@@ -187,10 +156,45 @@ class Decoder(srd.Decoder):
                  '(%2.1fus-%2.1fus) should be inside (7.3us, 10.0us).'
                  % (time_min * 1000000, time_max * 1000000)]])
 
+
+    def metadata(self, key, value):
+        if key != srd.SRD_CONF_SAMPLERATE:
+            return
+        self.samplerate = value
+
+        # The default 1-Wire time base is 30us. This is used to calculate
+        # sampling times.
+        samplerate = float(self.samplerate)
+
+        x = float(self.options['cnt_normal_bit']) / 1000000.0
+        self.cnt_normal_bit = int(samplerate * x) - 1
+        x = float(self.options['cnt_normal_slot']) / 1000000.0
+        self.cnt_normal_slot = int(samplerate * x) - 1
+        x = float(self.options['cnt_normal_presence']) / 1000000.0
+        self.cnt_normal_presence = int(samplerate * x) - 1
+        x = float(self.options['cnt_normal_reset']) / 1000000.0
+        self.cnt_normal_reset = int(samplerate * x) - 1
+        x = float(self.options['cnt_overdrive_bit']) / 1000000.0
+        self.cnt_overdrive_bit = int(samplerate * x) - 1
+        x = float(self.options['cnt_overdrive_slot']) / 1000000.0
+        self.cnt_overdrive_slot = int(samplerate * x) - 1
+        x = float(self.options['cnt_overdrive_presence']) / 1000000.0
+        self.cnt_overdrive_presence = int(samplerate * x) - 1
+        x = float(self.options['cnt_overdrive_reset']) / 1000000.0
+        self.cnt_overdrive_reset = int(samplerate * x) - 1
+
+        # Organize values into lists.
+        self.cnt_bit = [self.cnt_normal_bit, self.cnt_overdrive_bit]
+        self.cnt_presence = [self.cnt_normal_presence, self.cnt_overdrive_presence]
+        self.cnt_reset = [self.cnt_normal_reset, self.cnt_overdrive_reset]
+        self.cnt_slot = [self.cnt_normal_slot, self.cnt_overdrive_slot]
+
     def decode(self, ss, es, data):
         if not self.samplerate:
             raise SamplerateError('Cannot decode without samplerate.')
         for (self.samplenum, (owr, pwr)) in data:
+            if self.samplenum == 0:
+                self.checks()
             # State machine.
             if self.state == 'WAIT FOR FALLING EDGE':
                 # The start of a cycle is a falling edge.