- 'INVALID STOPBIT': The data is the (integer) value of the stop bit (0/1).
- 'PARITY ERROR': The data is a tuple with two entries. The first one is
the expected parity value, the second is the actual parity value.
- - TODO: Frame error?
+ - 'BREAK': The data is always 0.
+ - 'FRAME': The data is always a tuple containing two items: The (integer)
+ value of the UART data, and a boolean which reflects the validity of the
+ UART frame.
The <rxtx> field is 0 for RX packets, 1 for TX packets.
'''
license = 'gplv2+'
inputs = ['logic']
outputs = ['uart']
+ tags = ['Embedded/industrial']
optional_channels = (
# Allow specifying only one of the signals, e.g. if only one data
# direction exists (or is relevant).
'values': ('yes', 'no')},
{'id': 'invert_tx', 'desc': 'Invert TX?', 'default': 'no',
'values': ('yes', 'no')},
+ {'id': 'rx_packet_delimiter', 'desc': 'RX packet delimiter (decimal)',
+ 'default': -1},
+ {'id': 'tx_packet_delimiter', 'desc': 'TX packet delimiter (decimal)',
+ 'default': -1},
+ {'id': 'rx_packet_len', 'desc': 'RX packet length', 'default': -1},
+ {'id': 'tx_packet_len', 'desc': 'TX packet length', 'default': -1},
)
annotations = (
('rx-data', 'RX data'),
('tx-warnings', 'TX warnings'),
('rx-data-bits', 'RX data bits'),
('tx-data-bits', 'TX data bits'),
+ ('rx-break', 'RX break'),
+ ('tx-break', 'TX break'),
+ ('rx-packet', 'RX packet'),
+ ('tx-packet', 'TX packet'),
)
annotation_rows = (
('rx-data', 'RX', (0, 2, 4, 6, 8)),
('rx-data-bits', 'RX bits', (12,)),
('rx-warnings', 'RX warnings', (10,)),
+ ('rx-break', 'RX break', (14,)),
+ ('rx-packets', 'RX packets', (16,)),
('tx-data', 'TX', (1, 3, 5, 7, 9)),
('tx-data-bits', 'TX bits', (13,)),
('tx-warnings', 'TX warnings', (11,)),
+ ('tx-break', 'TX break', (15,)),
+ ('tx-packets', 'TX packets', (17,)),
)
binary = (
('rx', 'RX dump'),
s, halfbit = self.startsample[rxtx], self.bit_width / 2.0
self.put(s - floor(halfbit), self.samplenum + ceil(halfbit), self.out_ann, data)
+ def putx_packet(self, rxtx, data):
+ s, halfbit = self.ss_packet[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], self.bit_width / 2.0
self.put(s - floor(halfbit), self.samplenum + ceil(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 putgse(self, ss, es, data):
+ self.put(ss, es, self.out_ann, data)
+
+ def putpse(self, ss, es, data):
+ self.put(ss, es, self.out_python, data)
+
def putbin(self, rxtx, data):
s, halfbit = self.startsample[rxtx], self.bit_width / 2.0
self.put(s - floor(halfbit), self.samplenum + ceil(halfbit), self.out_binary, data)
self.samplerate = None
self.samplenum = 0
self.frame_start = [-1, -1]
+ self.frame_valid = [None, None]
self.startbit = [-1, -1]
self.cur_data_bit = [0, 0]
self.datavalue = [0, 0]
self.startsample = [-1, -1]
self.state = ['WAIT FOR START BIT', 'WAIT FOR START BIT']
self.databits = [[], []]
+ self.break_start = [None, None]
+ self.packet_cache = [[], []]
+ self.ss_packet, self.es_packet = [None, None], [None, None]
+ self.idle_start = [None, None]
def start(self):
self.out_python = self.register(srd.OUTPUT_PYTHON)
def wait_for_start_bit(self, rxtx, signal):
# Save the sample number where the start bit begins.
self.frame_start[rxtx] = self.samplenum
+ self.frame_valid[rxtx] = True
self.state[rxtx] = 'GET START BIT'
if self.startbit[rxtx] != 0:
self.putp(['INVALID STARTBIT', rxtx, self.startbit[rxtx]])
self.putg([rxtx + 10, ['Frame error', 'Frame err', 'FE']])
+ self.frame_valid[rxtx] = False
+ es = self.samplenum + ceil(self.bit_width / 2.0)
+ self.putpse(self.frame_start[rxtx], es, ['FRAME', rxtx,
+ (self.datavalue[rxtx], self.frame_valid[rxtx])])
self.state[rxtx] = 'WAIT FOR START BIT'
return
self.state[rxtx] = 'GET DATA BITS'
+ def handle_packet(self, rxtx):
+ d = 'rx' if (rxtx == RX) else 'tx'
+ delim = self.options[d + '_packet_delimiter']
+ plen = self.options[d + '_packet_len']
+ if delim == -1 and plen == -1:
+ return
+
+ # Cache data values until we see the delimiter and/or the specified
+ # packet length has been reached (whichever happens first).
+ if len(self.packet_cache[rxtx]) == 0:
+ self.ss_packet[rxtx] = self.startsample[rxtx]
+ self.packet_cache[rxtx].append(self.datavalue[rxtx])
+ if self.datavalue[rxtx] == delim or len(self.packet_cache[rxtx]) == plen:
+ self.es_packet[rxtx] = self.samplenum
+ s = ''
+ for b in self.packet_cache[rxtx]:
+ s += self.format_value(b)
+ if self.options['format'] != 'ascii':
+ s += ' '
+ if self.options['format'] != 'ascii' and s[-1] == ' ':
+ s = s[:-1] # Drop trailing space.
+ self.putx_packet(rxtx, [16 + rxtx, [s]])
+ self.packet_cache[rxtx] = []
+
def get_data_bits(self, rxtx, signal):
# Save the sample number of the middle of the first data bit.
if self.startsample[rxtx] == -1:
self.putbin(rxtx, [rxtx, bdata])
self.putbin(rxtx, [2, bdata])
+ self.handle_packet(rxtx)
+
self.databits[rxtx] = []
# Advance to either reception of the parity bit, or reception of
# TODO: Return expected/actual parity values.
self.putp(['PARITY ERROR', rxtx, (0, 1)]) # FIXME: Dummy tuple...
self.putg([rxtx + 6, ['Parity error', 'Parity err', 'PE']])
+ self.frame_valid[rxtx] = False
self.state[rxtx] = 'GET STOP BITS'
if self.stopbit1[rxtx] != 1:
self.putp(['INVALID STOPBIT', rxtx, self.stopbit1[rxtx]])
self.putg([rxtx + 10, ['Frame error', 'Frame err', 'FE']])
- # TODO: Abort? Ignore the frame? Other?
+ self.frame_valid[rxtx] = False
self.putp(['STOPBIT', rxtx, self.stopbit1[rxtx]])
self.putg([rxtx + 4, ['Stop bit', 'Stop', 'T']])
+ # Pass the complete UART frame to upper layers.
+ es = self.samplenum + ceil(self.bit_width / 2.0)
+ self.putpse(self.frame_start[rxtx], es, ['FRAME', rxtx,
+ (self.datavalue[rxtx], self.frame_valid[rxtx])])
+
+ self.state[rxtx] = 'WAIT FOR START BIT'
+ self.idle_start[rxtx] = self.frame_start[rxtx] + self.frame_len_sample_count
+
+ def handle_break(self, rxtx):
+ self.putpse(self.frame_start[rxtx], self.samplenum,
+ ['BREAK', rxtx, 0])
+ self.putgse(self.frame_start[rxtx], self.samplenum,
+ [rxtx + 14, ['Break condition', 'Break', 'Brk', 'B']])
self.state[rxtx] = 'WAIT FOR START BIT'
def get_wait_cond(self, rxtx, inv):
want_num = ceil(self.get_sample_point(rxtx, bitnum))
return {'skip': want_num - self.samplenum}
+ def get_idle_cond(self, rxtx, inv):
+ # Return a condition that corresponds to the (expected) end of
+ # the next frame, assuming that it will be an "idle frame"
+ # (constant high input level for the frame's length).
+ if self.idle_start[rxtx] is None:
+ return None
+ end_of_frame = self.idle_start[rxtx] + self.frame_len_sample_count
+ if end_of_frame < self.samplenum:
+ return None
+ return {'skip': end_of_frame - self.samplenum}
+
def inspect_sample(self, rxtx, signal, inv):
# Inspect a sample returned by .wait() for the specified UART line.
if inv:
elif state == 'GET STOP BITS':
self.get_stop_bits(rxtx, signal)
+ def inspect_edge(self, rxtx, signal, inv):
+ # Inspect edges, independently from traffic, to detect break conditions.
+ if inv:
+ signal = not signal
+ if not signal:
+ # Signal went low. Start another interval.
+ self.break_start[rxtx] = self.samplenum
+ return
+ # Signal went high. Was there an extended period with low signal?
+ if self.break_start[rxtx] is None:
+ return
+ diff = self.samplenum - self.break_start[rxtx]
+ if diff >= self.break_min_sample_count:
+ self.handle_break(rxtx)
+ self.break_start[rxtx] = None
+
+ def inspect_idle(self, rxtx, signal, inv):
+ # Check each edge and each period of stable input (either level).
+ # Can derive the "idle frame period has passed" condition.
+ if inv:
+ signal = not signal
+ if not signal:
+ # Low input, cease inspection.
+ self.idle_start[rxtx] = None
+ return
+ # High input, either just reached, or still stable.
+ if self.idle_start[rxtx] is None:
+ self.idle_start[rxtx] = self.samplenum
+ diff = self.samplenum - self.idle_start[rxtx]
+ if diff < self.frame_len_sample_count:
+ return
+ ss, es = self.idle_start[rxtx], self.samplenum
+ self.putpse(ss, es, ['IDLE', rxtx, 0])
+ self.idle_start[rxtx] = self.samplenum
+
def decode(self):
if not self.samplerate:
raise SamplerateError('Cannot decode without samplerate.')
opt = self.options
inv = [opt['invert_rx'] == 'yes', opt['invert_tx'] == 'yes']
- cond_idx = [None] * len(has_pin)
+ cond_data_idx = [None] * len(has_pin)
+
+ # Determine the number of samples for a complete frame's time span.
+ # A period of low signal (at least) that long is a break condition.
+ frame_samples = 1 # START
+ frame_samples += self.options['num_data_bits']
+ frame_samples += 0 if self.options['parity_type'] == 'none' else 1
+ frame_samples += self.options['num_stop_bits']
+ frame_samples *= self.bit_width
+ self.frame_len_sample_count = ceil(frame_samples)
+ self.break_min_sample_count = self.frame_len_sample_count
+ cond_edge_idx = [None] * len(has_pin)
+ cond_idle_idx = [None] * len(has_pin)
while True:
conds = []
if has_pin[RX]:
- cond_idx[RX] = len(conds)
+ cond_data_idx[RX] = len(conds)
conds.append(self.get_wait_cond(RX, inv[RX]))
+ cond_edge_idx[RX] = len(conds)
+ conds.append({RX: 'e'})
+ cond_idle_idx[RX] = None
+ idle_cond = self.get_idle_cond(RX, inv[RX])
+ if idle_cond:
+ cond_idle_idx[RX] = len(conds)
+ conds.append(idle_cond)
if has_pin[TX]:
- cond_idx[TX] = len(conds)
+ cond_data_idx[TX] = len(conds)
conds.append(self.get_wait_cond(TX, inv[TX]))
+ cond_edge_idx[TX] = len(conds)
+ conds.append({TX: 'e'})
+ cond_idle_idx[TX] = None
+ idle_cond = self.get_idle_cond(TX, inv[TX])
+ if idle_cond:
+ cond_idle_idx[TX] = len(conds)
+ conds.append(idle_cond)
(rx, tx) = self.wait(conds)
- if cond_idx[RX] is not None and self.matched[cond_idx[RX]]:
+ if cond_data_idx[RX] is not None and self.matched[cond_data_idx[RX]]:
self.inspect_sample(RX, rx, inv[RX])
- if cond_idx[TX] is not None and self.matched[cond_idx[TX]]:
+ if cond_edge_idx[RX] is not None and self.matched[cond_edge_idx[RX]]:
+ self.inspect_edge(RX, rx, inv[RX])
+ self.inspect_idle(RX, rx, inv[RX])
+ if cond_idle_idx[RX] is not None and self.matched[cond_idle_idx[RX]]:
+ self.inspect_idle(RX, rx, inv[RX])
+ if cond_data_idx[TX] is not None and self.matched[cond_data_idx[TX]]:
self.inspect_sample(TX, tx, inv[TX])
+ if cond_edge_idx[TX] is not None and self.matched[cond_edge_idx[TX]]:
+ self.inspect_edge(TX, tx, inv[TX])
+ self.inspect_idle(TX, tx, inv[TX])
+ if cond_idle_idx[TX] is not None and self.matched[cond_idle_idx[TX]]:
+ self.inspect_idle(TX, tx, inv[TX])
projects / libsigrokdecode.git / blobdiff