-lastsample = None
-oldbit = None
-transitions = None
-rising = None
-falling = None
-
-def decode(sampledata):
- """Counts the low->high and high->low transitions in the specified
- channel(s) of the signal."""
- global lastsample
- global oldbit, transitions, rising, falling
-
- # TODO: Don't hardcode the number of channels.
- channels = 8
-
- # FIXME: Get the data in the correct format in the first place.
- inbuf = [ord(x) for x in sampledata['data']]
-
- if lastsample == None:
- oldbit = [0] * channels
- transitions = [0] * channels
- rising = [0] * channels
- falling = [0] * channels
-
- # Initial values.
- lastsample = inbuf[0]
- for i in range(channels):
- oldbit[i] = (lastsample & (1 << i)) >> i
-
- # TODO: Handle LAs with more/less than 8 channels.
- for s in inbuf:
- # Optimization: Skip identical bytes (no transitions).
- if lastsample != s:
- for i in range(channels):
+class Sample():
+ def __init__(self, data):
+ self.data = data
+ def probe(self, probe):
+ s = ord(self.data[probe / 8]) & (1 << (probe % 8))
+ return True if s else False
+
+def sampleiter(data, unitsize):
+ for i in range(0, len(data), unitsize):
+ yield(Sample(data[i:i+unitsize]))
+
+class Decoder(sigrok.Decoder):
+ id = 'transitioncounter'
+ name = 'Transition counter'
+ longname = '...'
+ desc = 'Counts rising/falling edges in the signal.'
+ longdesc = '...'
+ author = 'Uwe Hermann'
+ email = 'uwe@hermann-uwe.de'
+ license = 'gplv2+'
+ inputs = ['logic']
+ outputs = ['transitioncounts']
+ probes = {}
+ options = {}
+
+ def __init__(self, **kwargs):
+ self.probes = Decoder.probes.copy()
+
+ # TODO: Don't hardcode the number of channels.
+ self.channels = 8
+
+ self.lastsample = None
+ self.oldbit = [0] * self.channels
+ self.transitions = [0] * self.channels
+ self.rising = [0] * self.channels
+ self.falling = [0] * self.channels
+
+ def start(self, metadata):
+ self.unitsize = metadata['unitsize']
+
+ def report(self):
+ pass
+
+ def decode(self, data):
+ """Counts the low->high and high->low transitions in the specified
+ channel(s) of the signal."""
+
+ # We should accept a list of samples and iterate...
+ for sample in sampleiter(data['data'], self.unitsize):
+
+ # TODO: Eliminate the need for ord().
+ s = ord(sample.data)
+
+ # Optimization: Skip identical samples (no transitions).
+ if self.lastsample == s:
+ continue
+
+ # Upon the first sample, store the initial values.
+ if self.lastsample == None:
+ self.lastsample = s
+ for i in range(self.channels):
+ self.oldbit[i] = (self.lastsample & (1 << i)) >> i
+
+ # Iterate over all channels/probes in this sample.
+ # Count rising and falling edges for each channel.
+ for i in range(self.channels):