X-Git-Url: https://sigrok.org/gitweb/?p=libsigrokdecode.git;a=blobdiff_plain;f=decoders%2Fcounter%2Fpd.py;h=b8811e589bdf89e58ae8748435b536016f490be9;hp=23cbd9781b5a5618bf95ce1fdf938c8a6f801f5e;hb=e663ab183cc55fbff23da01c0fda06d366b7130b;hpb=647d52869813b2df8ee82837f17681a77d0521e0

diff --git a/decoders/counter/pd.py b/decoders/counter/pd.py
index 23cbd97..b8811e5 100644
--- a/decoders/counter/pd.py
+++ b/decoders/counter/pd.py
@@ -19,8 +19,8 @@
 
 import sigrokdecode as srd
 
-(PIN_DATA, PIN_RESET) = range(2)
-(ROW_EDGE, ROW_WORD, ROW_RESET) = range(3)
+PIN_DATA, PIN_RESET = range(2)
+ROW_EDGE, ROW_WORD, ROW_RESET = range(3)
 
 class Decoder(srd.Decoder):
     api_version = 3
@@ -53,6 +53,8 @@ class Decoder(srd.Decoder):
         {'id': 'divider', 'desc': 'Count divider (word width)', 'default': 0},
         {'id': 'reset_edge', 'desc': 'Edge which clears counters (reset)',
             'default': 'falling', 'values': ('rising', 'falling')},
+        {'id': 'edge_off', 'desc': 'Initial edge counter value', 'default': 0},
+        {'id': 'word_off', 'desc': 'Initial word counter value', 'default': 0},
     )
 
     def __init__(self):
@@ -86,21 +88,40 @@ class Decoder(srd.Decoder):
             cond_reset = len(condition)
             condition.append({PIN_RESET: opt_edge_map[reset_edge]})
 
-        edge_count = 0
-        word_count = 0
+        edge_count = int(self.options['edge_off'])
+        edge_start = None
+        word_count = int(self.options['word_off'])
+        word_start = None
         while True:
             self.wait(condition)
             now = self.samplenum
 
             if have_reset and self.matched[cond_reset]:
                 edge_count = 0
+                edge_start = now
                 word_count = 0
+                word_start = now
                 self.putc(ROW_RESET, now, ['Word reset', 'Reset', 'Rst', 'R'])
                 continue
 
+            # Implementation note: In the absence of a RESET condition
+            # before the first data edge, any arbitrary choice of where
+            # to start the annotation is valid. One may choose to emit a
+            # narrow annotation (where ss=es), or assume that the cycle
+            # which corresponds to the counter value started at sample
+            # number 0. We decided to go with the latter here, to avoid
+            # narrow annotations (see bug #1210). None of this matters in
+            # the presence of a RESET condition in the input stream.
+            if edge_start is None:
+                edge_start = 0
+            if word_start is None:
+                word_start = 0
+
             edge_count += 1
-            self.putc(ROW_EDGE, now, ["{:d}".format(edge_count)])
+            self.putc(ROW_EDGE, edge_start, ["{:d}".format(edge_count)])
+            edge_start = now
 
             if divider and (edge_count % divider) == 0:
                 word_count += 1
-                self.putc(ROW_WORD, now, ["{:d}".format(word_count)])
+                self.putc(ROW_WORD, word_start, ["{:d}".format(word_count)])
+                word_start = now