diff options
Diffstat (limited to 'decoders/usb_signalling')
| -rw-r--r-- | decoders/usb_signalling/pd.py | 17 |
1 files changed, 14 insertions, 3 deletions
diff --git a/decoders/usb_signalling/pd.py b/decoders/usb_signalling/pd.py index 8225ae7..cea579a 100644 --- a/decoders/usb_signalling/pd.py +++ b/decoders/usb_signalling/pd.py @@ -148,6 +148,7 @@ class Decoder(srd.Decoder): self.oldpins = None self.edgepins = None self.consecutive_ones = 0 + self.bits = None self.state = 'INIT' def start(self): @@ -200,6 +201,7 @@ class Decoder(srd.Decoder): if sym != 'K' or self.oldsym != 'J': return self.consecutive_ones = 0 + self.bits = "" self.update_bitrate() self.samplepos = self.samplenum - (self.bitwidth / 2) + 0.5 self.set_new_target_samplenum() @@ -247,16 +249,26 @@ class Decoder(srd.Decoder): def get_bit(self, sym): self.set_new_target_samplenum() + b = '0' if self.oldsym != sym else '1' + self.oldsym = sym if sym == 'SE0': # Start of an EOP. Change state, save edge self.state = 'GET EOP' self.ss_block = self.samplenum_lastedge else: - b = '0' if self.oldsym != sym else '1' self.handle_bit(b) self.putpb(['SYM', sym]) self.putb(sym_annotation[sym]) - if self.oldsym != sym: + if len(self.bits) <= 16: + self.bits += b + if len(self.bits) == 16 and self.bits == '0000000100111100': + # Sync and low-speed PREamble seen + self.putpx(['EOP', None]) + self.state = 'IDLE' + self.signalling = 'low-speed-rp' + self.update_bitrate() + self.oldsym = 'J' + if b == '0': edgesym = symbols[self.signalling][tuple(self.edgepins)] if edgesym not in ('SE0', 'SE1'): if edgesym == sym: @@ -265,7 +277,6 @@ class Decoder(srd.Decoder): else: self.bitwidth = self.bitwidth + (0.001 * self.bitwidth) self.samplepos = self.samplepos + (0.01 * self.bitwidth) - self.oldsym = sym def handle_idle(self, sym): self.samplenum_edge = self.samplenum |