2 ## This file is part of the sigrok project.
4 ## Copyright (C) 2010 Uwe Hermann <uwe@hermann-uwe.de>
6 ## This program is free software; you can redistribute it and/or modify
7 ## it under the terms of the GNU General Public License as published by
8 ## the Free Software Foundation; either version 2 of the License, or
9 ## (at your option) any later version.
11 ## This program is distributed in the hope that it will be useful,
12 ## but WITHOUT ANY WARRANTY; without even the implied warranty of
13 ## MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 ## GNU General Public License for more details.
16 ## You should have received a copy of the GNU General Public License
17 ## along with this program; if not, write to the Free Software
18 ## Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
23 class Decoder(sigrokdecode.Decoder):
24 id = 'transitioncounter'
25 name = 'Transition counter'
27 desc = 'Counts rising/falling edges in the signal.'
29 author = 'Uwe Hermann'
30 email = 'uwe@hermann-uwe.de'
33 outputs = ['transitioncounts']
38 def __init__(self, **kwargs):
42 self.lastsample = None
44 def start(self, metadata):
45 # self.out_proto = self.add(sigrokdecode.SRD_OUTPUT_PROTO, 'transitioncounter')
46 self.out_ann = self.add(sigrokdecode.SRD_OUTPUT_ANN, 'transitioncounter')
51 def decode(self, timeoffset, duration, data):
53 for (samplenum, s) in data:
56 if self.channels == -1:
57 self.channels = len(s)
58 self.oldbit = [0] * self.channels
59 self.transitions = [0] * self.channels
60 self.rising = [0] * self.channels
61 self.falling = [0] * self.channels
63 # Optimization: Skip identical samples (no transitions).
64 if self.lastsample == s:
67 # Upon the first sample, store the initial values.
68 if self.lastsample == None:
70 for i in range(self.channels):
71 self.oldbit[i] = self.lastsample[i]
73 # Iterate over all channels/probes in this sample.
74 # Count rising and falling edges for each channel.
75 for i in range(self.channels):
77 # Optimization: Skip identical bits (no transitions).
78 if self.oldbit[i] == curbit:
80 elif (self.oldbit[i] == 0 and curbit == 1):
82 elif (self.oldbit[i] == 1 and curbit == 0):
84 self.oldbit[i] = curbit
86 # Save the current sample as 'lastsample' for the next round.
89 # Total number of transitions = rising + falling edges.
90 for i in range(self.channels):
91 self.transitions[i] = self.rising[i] + self.falling[i]
93 # TODO: Which output format?
94 # TODO: How to only output something after the last chunk of data?
96 for i in range(self.channels):
97 outdata += [[self.transitions[i], self.rising[i], self.falling[i]]]
100 # self.put(0, 0, self.out_proto, out_proto)
101 self.put(0, 0, self.out_ann, outdata)