##
import sigrokdecode as srd
+from math import floor, ceil
'''
OUTPUT_PYTHON format:
This is the list of <ptype>s and their respective <pdata> values:
- 'STARTBIT': The data is the (integer) value of the start bit (0/1).
- - 'DATA': The data is the (integer) value of the UART data. Valid values
- range from 0 to 512 (as the data can be up to 9 bits in size).
- - 'DATABITS': List of data bits and their ss/es numbers.
+ - 'DATA': This is always a tuple containing two items:
+ - 1st item: the (integer) value of the UART data. Valid values
+ range from 0 to 512 (as the data can be up to 9 bits in size).
+ - 2nd item: the list of individual data bits and their ss/es numbers.
- 'PARITYBIT': The data is the (integer) value of the parity bit (0/1).
- 'STOPBIT': The data is the (integer) value of the stop bit (0 or 1).
- 'INVALID STARTBIT': The data is the (integer) value of the start bit (0/1).
return (ones % 2) == 1
elif parity_type == 'even':
return (ones % 2) == 0
- else:
- raise Exception('Invalid parity type: %d' % parity_type)
+
+class SamplerateError(Exception):
+ pass
+
+class ChannelError(Exception):
+ pass
class Decoder(srd.Decoder):
api_version = 2
'values': ('lsb-first', 'msb-first')},
{'id': 'format', 'desc': 'Data format', 'default': 'ascii',
'values': ('ascii', 'dec', 'hex', 'oct', 'bin')},
- # TODO: Options to invert the signal(s).
+ {'id': 'invert_rx', 'desc': 'Invert RX?', 'default': 'no',
+ 'values': ('yes', 'no')},
+ {'id': 'invert_tx', 'desc': 'Invert TX?', 'default': 'no',
+ 'values': ('yes', 'no')},
)
annotations = (
('rx-data', 'RX data'),
)
def putx(self, rxtx, data):
- s, halfbit = self.startsample[rxtx], int(self.bit_width / 2)
- self.put(s - halfbit, self.samplenum + halfbit, self.out_ann, data)
+ s, halfbit = self.startsample[rxtx], self.bit_width / 2.0
+ self.put(s - floor(halfbit), self.samplenum + ceil(halfbit), self.out_ann, data)
def putpx(self, rxtx, data):
- s, halfbit = self.startsample[rxtx], int(self.bit_width / 2)
- self.put(s - halfbit, self.samplenum + halfbit, self.out_python, data)
+ s, halfbit = self.startsample[rxtx], self.bit_width / 2.0
+ self.put(s - floor(halfbit), self.samplenum + ceil(halfbit), self.out_python, data)
def putg(self, data):
- s, halfbit = self.samplenum, int(self.bit_width / 2)
- self.put(s - halfbit, s + halfbit, self.out_ann, data)
+ s, halfbit = self.samplenum, self.bit_width / 2.0
+ self.put(s - floor(halfbit), s + ceil(halfbit), self.out_ann, data)
def putp(self, data):
- s, halfbit = self.samplenum, int(self.bit_width / 2)
- self.put(s - halfbit, s + halfbit, self.out_python, data)
+ s, halfbit = self.samplenum, self.bit_width / 2.0
+ self.put(s - floor(halfbit), s + ceil(halfbit), self.out_python, data)
def putbin(self, rxtx, data):
- s, halfbit = self.startsample[rxtx], int(self.bit_width / 2)
- self.put(s - halfbit, self.samplenum + halfbit, self.out_bin, data)
+ s, halfbit = self.startsample[rxtx], self.bit_width / 2.0
+ self.put(s - floor(halfbit), self.samplenum + ceil(halfbit), self.out_bin, data)
def __init__(self, **kwargs):
self.samplerate = None
def metadata(self, key, value):
if key == srd.SRD_CONF_SAMPLERATE:
- self.samplerate = value;
+ self.samplerate = value
# The width of one UART bit in number of samples.
self.bit_width = float(self.samplerate) / float(self.options['baudrate'])
# bitpos is the samplenumber which is in the middle of the
# specified UART bit (0 = start bit, 1..x = data, x+1 = parity bit
# (if used) or the first stop bit, and so on).
- bitpos = self.frame_start[rxtx] + (self.bit_width / 2.0)
+ # The samples within bit are 0, 1, ..., (bit_width - 1), therefore
+ # index of the middle sample within bit window is (bit_width - 1) / 2.
+ bitpos = self.frame_start[rxtx] + (self.bit_width - 1) / 2.0
bitpos += bitnum * self.bit_width
if self.samplenum >= bitpos:
return True
self.databyte[rxtx] >>= 1
self.databyte[rxtx] |= \
(signal << (self.options['num_data_bits'] - 1))
- elif self.options['bit_order'] == 'msb-first':
+ else:
self.databyte[rxtx] <<= 1
self.databyte[rxtx] |= (signal << 0)
- else:
- raise Exception('Invalid bit order value: %s',
- self.options['bit_order'])
self.putg([rxtx + 12, ['%d' % signal]])
self.state[rxtx] = 'GET PARITY BIT'
- self.putpx(rxtx, ['DATABITS', rxtx, self.databits[rxtx]])
- self.putpx(rxtx, ['DATA', rxtx, self.databyte[rxtx]])
+ self.putpx(rxtx, ['DATA', rxtx,
+ (self.databyte[rxtx], self.databits[rxtx])])
b, f = self.databyte[rxtx], self.options['format']
if f == 'ascii':
self.putx(rxtx, [rxtx, [oct(b)[2:].zfill(3)]])
elif f == 'bin':
self.putx(rxtx, [rxtx, [bin(b)[2:].zfill(8)]])
- else:
- raise Exception('Invalid data format option: %s' % f)
self.putbin(rxtx, (rxtx, bytes([b])))
self.putbin(rxtx, (2, bytes([b])))
self.putg([rxtx + 4, ['Stop bit', 'Stop', 'T']])
def decode(self, ss, es, data):
- if self.samplerate is None:
- raise Exception("Cannot decode without samplerate.")
+ if not self.samplerate:
+ raise SamplerateError('Cannot decode without samplerate.')
for (self.samplenum, pins) in data:
# Note: Ignoring identical samples here for performance reasons
# continue
self.oldpins, (rx, tx) = pins, pins
+ if self.options['invert_rx'] == 'yes':
+ rx = not rx
+ if self.options['invert_tx'] == 'yes':
+ tx = not tx
+
# Either RX or TX (but not both) can be omitted.
has_pin = [rx in (0, 1), tx in (0, 1)]
if has_pin == [False, False]:
- raise Exception('Either TX or RX (or both) pins required.')
+ raise ChannelError('Either TX or RX (or both) pins required.')
# State machine.
for rxtx in (RX, TX):
# Save current RX/TX values for the next round.
self.oldbit[rxtx] = signal
-
projects / libsigrokdecode.git / blobdiff