## Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
##
-# Bitrate / baudrate guessing protocol decoder
-
import sigrokdecode as srd
+class SamplerateError(Exception):
+ pass
+
class Decoder(srd.Decoder):
- api_version = 1
+ api_version = 2
id = 'guess_bitrate'
name = 'Guess bitrate'
longname = 'Guess bitrate/baudrate'
license = 'gplv2+'
inputs = ['logic']
outputs = ['guess_bitrate']
- probes = [
+ channels = (
{'id': 'data', 'name': 'Data', 'desc': 'Data line'},
- ]
- optional_probes = []
- options = {}
- annotations = [
- ['bitrate', 'Bitrate / baudrate'],
- ]
+ )
+ annotations = (
+ ('bitrate', 'Bitrate / baudrate'),
+ )
def putx(self, data):
self.put(self.ss_edge, self.samplenum, self.out_ann, data)
self.first_transition = True
self.bitwidth = None
- def start(self, metadata):
- self.samplerate = metadata['samplerate']
- # self.out_proto = self.register(srd.OUTPUT_PYTHON)
+ def start(self):
self.out_ann = self.register(srd.OUTPUT_ANN)
- def report(self):
- pass
+ def metadata(self, key, value):
+ if key == srd.SRD_CONF_SAMPLERATE:
+ self.samplerate = value
def decode(self, ss, es, data):
+ if not self.samplerate:
+ raise SamplerateError('Cannot decode without samplerate.')
for (self.samplenum, pins) in data:
data = pins[0]
continue
# Initialize first self.olddata with the first sample value.
- if self.olddata == None:
+ if self.olddata is None:
self.olddata = data
continue
# Get the smallest distance between two transitions
# and use that to calculate the bitrate/baudrate.
- if self.first_transition == True:
+ if self.first_transition:
self.ss_edge = self.samplenum
self.first_transition = False
else:
b = self.samplenum - self.ss_edge
- if self.bitwidth == None or b < self.bitwidth:
+ if self.bitwidth is None or b < self.bitwidth:
self.bitwidth = b
bitrate = int(float(self.samplerate) / float(b))
self.putx([0, ['%d' % bitrate]])
self.ss_edge = self.samplenum
self.olddata = data
-