diff options
| -rw-r--r-- | decoders/usb_signalling/pd.py | 16 |
1 files changed, 10 insertions, 6 deletions
diff --git a/decoders/usb_signalling/pd.py b/decoders/usb_signalling/pd.py index 75069f4..70ada37 100644 --- a/decoders/usb_signalling/pd.py +++ b/decoders/usb_signalling/pd.py @@ -40,6 +40,11 @@ symbols_fs = { (1, 1): 'SE1', } +bitrates = { + 'low-speed': 1500000, # 1.5Mb/s (+/- 1.5%) + 'full-speed': 12000000, # 12Mb/s (+/- 0.25%) +} + class Decoder(srd.Decoder): api_version = 1 id = 'usb_signalling' @@ -67,12 +72,15 @@ class Decoder(srd.Decoder): self.scount = 0 self.packet = '' self.syms = [] + self.bitrate = None + self.bitwidth = None self.oldpins = None def start(self, metadata): - self.samplerate = metadata['samplerate'] self.out_proto = self.add(srd.OUTPUT_PROTO, 'usb_signalling') self.out_ann = self.add(srd.OUTPUT_ANN, 'usb_signalling') + self.bitrate = bitrates[self.options['signalling']] + self.bitwidth = float(metadata['samplerate']) / float(self.bitrate) def report(self): pass @@ -117,11 +125,7 @@ class Decoder(srd.Decoder): # How many bits since the last transition? if self.packet != '' or self.sym != 'J': - if self.options['signalling'] == 'low-speed': - bitrate = 1500000 # 1.5Mb/s (+/- 1.5%) - elif self.options['signalling'] == 'full-speed': - bitrate = 12000000 # 12Mb/s (+/- 0.25%) - bitcount = int((self.scount - 1) * bitrate / self.samplerate) + bitcount = int((self.scount - 1) / self.bitwidth) else: bitcount = 0 |