+ def handle_idle(self, sym):
+ self.samplenum_edge = self.samplenum
+ se0_length = float(self.samplenum - self.samplenum_lastedge) / self.samplerate
+ if se0_length > 2.5e-6: # 2.5us
+ self.putpb(['RESET', None])
+ self.putb([10, ['Reset', 'Res', 'R']])
+ self.signalling = self.options['signalling']
+ elif se0_length > 1.2e-6 and self.signalling == 'low-speed':
+ self.putpb(['KEEP ALIVE', None])
+ self.putb([9, ['Keep-alive', 'KA', 'A']])
+
+ if sym == 'FS_J':
+ self.signalling = 'full-speed'
+ self.update_bitrate()
+ elif sym == 'LS_J':
+ self.signalling = 'low-speed'
+ self.update_bitrate()
+ self.oldsym = 'J'
+ self.state = 'IDLE'
+
+ def decode(self, ss, es, data):
+ if not self.samplerate:
+ raise SamplerateError('Cannot decode without samplerate.')
+ for (self.samplenum, pins) in data:
+ # State machine.
+ if self.state == 'IDLE':
+ # Ignore identical samples early on (for performance reasons).
+ if self.oldpins == pins:
+ continue
+ self.oldpins = pins
+ sym = symbols[self.signalling][tuple(pins)]
+ if sym == 'SE0':
+ self.samplenum_lastedge = self.samplenum
+ self.state = 'WAIT IDLE'
+ else:
+ self.wait_for_sop(sym)
+ self.edgepins = pins
+ elif self.state in ('GET BIT', 'GET EOP'):
+ # Wait until we're in the middle of the desired bit.
+ if self.samplenum == self.samplenum_edge:
+ self.edgepins = pins
+ if self.samplenum < self.samplenum_target:
+ continue
+ sym = symbols[self.signalling][tuple(pins)]
+ if self.state == 'GET BIT':
+ self.get_bit(sym)
+ elif self.state == 'GET EOP':
+ self.get_eop(sym)
+ self.oldpins = pins
+ elif self.state == 'WAIT IDLE':
+ if tuple(pins) == (0, 0):
+ continue
+ if self.samplenum - self.samplenum_lastedge > 1:
+ sym = symbols[self.options['signalling']][tuple(pins)]
+ self.handle_idle(sym)
+ else:
+ sym = symbols[self.signalling][tuple(pins)]
+ self.wait_for_sop(sym)
+ self.oldpins = pins
+ self.edgepins = pins
+ elif self.state == 'INIT':
+ sym = symbols[self.options['signalling']][tuple(pins)]
+ self.handle_idle(sym)
+ self.oldpins = pins