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
21 # Transition counter protocol decoder
23 import sigrokdecode as srd
25 class Decoder(srd.Decoder):
27 id = 'transitioncounter'
28 name = 'Transition counter'
29 longname = 'Pin transition counter'
30 desc = 'Counts rising/falling edges in the signal.'
33 outputs = ['transitioncounts']
41 def __init__(self, **kwargs):
43 self.lastsample = None
45 def start(self, metadata):
46 # self.out_proto = self.add(srd.OUTPUT_PROTO, 'transitioncounter')
47 self.out_ann = self.add(srd.OUTPUT_ANN, 'transitioncounter')
52 def decode(self, ss, es, data):
54 for (samplenum, s) in data:
57 if self.channels == -1:
58 self.channels = len(s)
59 self.oldbit = [0] * self.channels
60 self.transitions = [0] * self.channels
61 self.rising = [0] * self.channels
62 self.falling = [0] * self.channels
64 # Optimization: Skip identical samples (no transitions).
65 if self.lastsample == s:
68 # Upon the first sample, store the initial values.
69 if self.lastsample == None:
71 for i in range(self.channels):
72 self.oldbit[i] = self.lastsample[i]
74 # Iterate over all channels/probes in this sample.
75 # Count rising and falling edges for each channel.
76 for i in range(self.channels):
78 # Optimization: Skip identical bits (no transitions).
79 if self.oldbit[i] == curbit:
81 elif (self.oldbit[i] == 0 and curbit == 1):
83 elif (self.oldbit[i] == 1 and curbit == 0):
85 self.oldbit[i] = curbit
87 # Save the current sample as 'lastsample' for the next round.
90 # Total number of transitions = rising + falling edges.
91 for i in range(self.channels):
92 self.transitions[i] = self.rising[i] + self.falling[i]
94 # TODO: Which output format?
95 # TODO: How to only output something after the last chunk of data?
97 for i in range(self.channels):
98 outdata.append([self.transitions[i], self.rising[i],
102 # self.put(0, 0, self.out_proto, out_proto)
103 self.put(0, 0, self.out_ann, [0, [str(outdata)]])