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.'
34 outputs = ['transitioncounts']
42 def __init__(self, **kwargs):
44 self.lastsample = None
46 def start(self, metadata):
47 # self.out_proto = self.add(srd.OUTPUT_PROTO, 'transitioncounter')
48 self.out_ann = self.add(srd.OUTPUT_ANN, 'transitioncounter')
53 def decode(self, ss, es, data):
55 for (samplenum, s) in data:
58 if self.channels == -1:
59 self.channels = len(s)
60 self.oldbit = [0] * self.channels
61 self.transitions = [0] * self.channels
62 self.rising = [0] * self.channels
63 self.falling = [0] * self.channels
65 # Optimization: Skip identical samples (no transitions).
66 if self.lastsample == s:
69 # Upon the first sample, store the initial values.
70 if self.lastsample == None:
72 for i in range(self.channels):
73 self.oldbit[i] = self.lastsample[i]
75 # Iterate over all channels/probes in this sample.
76 # Count rising and falling edges for each channel.
77 for i in range(self.channels):
79 # Optimization: Skip identical bits (no transitions).
80 if self.oldbit[i] == curbit:
82 elif (self.oldbit[i] == 0 and curbit == 1):
84 elif (self.oldbit[i] == 1 and curbit == 0):
86 self.oldbit[i] = curbit
88 # Save the current sample as 'lastsample' for the next round.
91 # Total number of transitions = rising + falling edges.
92 for i in range(self.channels):
93 self.transitions[i] = self.rising[i] + self.falling[i]
95 # TODO: Which output format?
96 # TODO: How to only output something after the last chunk of data?
98 for i in range(self.channels):
99 outdata.append([self.transitions[i], self.rising[i],
103 # self.put(0, 0, self.out_proto, out_proto)
104 self.put(0, 0, self.out_ann, [0, [str(outdata)]])