X-Git-Url: http://sigrok.org/gitweb/?a=blobdiff_plain;f=decoders%2Fcan%2Fpd.py;h=3dbadc090313cc424feaf13051cf724e82c29108;hb=6ca8b2b761788a1a2476fc4de3899f456428a277;hp=292f51b650e97a7789809737a14899740e1043a2;hpb=3b593817d2824d925952c22321ee3ec2442c299c;p=libsigrokdecode.git diff --git a/decoders/can/pd.py b/decoders/can/pd.py index 292f51b..3dbadc0 100644 --- a/decoders/can/pd.py +++ b/decoders/can/pd.py @@ -23,6 +23,9 @@ import sigrokdecode as srd class SamplerateError(Exception): pass +def dlc2len(dlc): + return [0, 1, 2, 3, 4, 5, 6, 7, 8, 12, 16, 20, 24, 32, 48, 64][dlc] + class Decoder(srd.Decoder): api_version = 3 id = 'can' @@ -42,7 +45,7 @@ class Decoder(srd.Decoder): {'id': 'sample_point', 'desc': 'Sample point (%)', 'default': 70.0}, ) annotations = ( - ('data', 'CAN payload data'), + ('data', 'Payload data'), ('sof', 'Start of frame'), ('eof', 'End of frame'), ('id', 'Identifier'), @@ -58,7 +61,7 @@ class Decoder(srd.Decoder): ('ack-slot', 'ACK slot'), ('ack-delimiter', 'ACK delimiter'), ('stuff-bit', 'Stuff bit'), - ('warnings', 'Human-readable warnings'), + ('warning', 'Warning'), ('bit', 'Bit'), ) annotation_rows = ( @@ -70,9 +73,6 @@ class Decoder(srd.Decoder): def __init__(self): self.reset() - def dlc2len(self, dlc): - return [0, 1, 2, 3, 4, 5, 6, 7, 8, 12, 16, 20, 24, 32, 48, 64][dlc] - def reset(self): self.samplerate = None self.reset_variables() @@ -80,6 +80,16 @@ class Decoder(srd.Decoder): def start(self): self.out_ann = self.register(srd.OUTPUT_ANN) + def set_bit_rate(self, bitrate): + self.bit_width = float(self.samplerate) / float(bitrate) + self.sample_point = (self.bit_width / 100.0) * self.options['sample_point'] + + def set_nominal_bitrate(self): + self.set_bit_rate(self.options['nominal_bitrate']) + + def set_fast_bitrate(self): + self.set_bit_rate(self.options['fast_bitrate']) + def metadata(self, key, value): if key == srd.SRD_CONF_SAMPLERATE: self.samplerate = value @@ -130,16 +140,12 @@ class Decoder(srd.Decoder): self.dom_edge_snum = self.samplenum self.dom_edge_bcount = self.curbit - def bit_sampled(self): - # EMPTY - pass - # Determine the position of the next desired bit's sample point. def get_sample_point(self, bitnum): samplenum = self.dom_edge_snum - samplenum += int(self.bit_width * (bitnum - self.dom_edge_bcount)) - samplenum += int(self.sample_point) - return samplenum + samplenum += self.bit_width * (bitnum - self.dom_edge_bcount) + samplenum += self.sample_point + return int(samplenum) def is_stuff_bit(self): # CAN uses NRZ encoding and bit stuffing. @@ -173,7 +179,7 @@ class Decoder(srd.Decoder): if bitnum == (self.last_databit + 1): self.ss_block = self.samplenum if self.fd: - if self.dlc2len(self.dlc) < 16: + if dlc2len(self.dlc) < 16: self.crc_len = 27 # 17 + SBC + stuff bits else: self.crc_len = 32 # 21 + SBC + stuff bits @@ -183,12 +189,12 @@ class Decoder(srd.Decoder): # CRC sequence (15 bits, 17 bits or 21 bits) elif bitnum == (self.last_databit + self.crc_len): if self.fd: - if self.dlc2len(self.dlc) < 16: + if dlc2len(self.dlc) < 16: crc_type = "CRC-17" else: crc_type = "CRC-21" else: - crc_type = "CRC" # TODO: CRC-15 (will break existing tests) + crc_type = "CRC-15" x = self.last_databit + 1 crc_bits = self.bits[x:x + self.crc_len + 1] @@ -205,6 +211,9 @@ class Decoder(srd.Decoder): if can_rx != 1: self.putx([16, ['CRC delimiter must be a recessive bit']]) + if self.fd: + self.set_nominal_bitrate() + # ACK slot bit (dominant: ACK, recessive: NACK) elif bitnum == (self.last_databit + self.crc_len + 2): ack = 'ACK' if can_rx == 0 else 'NACK' @@ -277,7 +286,7 @@ class Decoder(srd.Decoder): self.dlc = int(''.join(str(d) for d in self.bits[self.dlc_start:self.dlc_start + 4]), 2) self.putb([10, ['Data length code: %d' % self.dlc, 'DLC: %d' % self.dlc, 'DLC']]) - self.last_databit = self.dlc_start + 3 + (self.dlc2len(self.dlc) * 8) + self.last_databit = self.dlc_start + 3 + (dlc2len(self.dlc) * 8) if self.dlc > 8 and not self.fd: self.putb([16, ['Data length code (DLC) > 8 is not allowed']]) @@ -289,7 +298,7 @@ class Decoder(srd.Decoder): # The bits within a data byte are transferred MSB-first. elif bitnum == self.last_databit: self.ss_databytebits.append(self.samplenum) # Last databyte bit. - for i in range(self.dlc2len(self.dlc)): + for i in range(dlc2len(self.dlc)): x = self.dlc_start + 4 + (8 * i) b = int(''.join(str(d) for d in self.bits[x:x + 8]), 2) ss = self.ss_databytebits[i * 8] @@ -377,7 +386,7 @@ class Decoder(srd.Decoder): self.dlc = int(''.join(str(d) for d in self.bits[self.dlc_start:self.dlc_start + 4]), 2) self.putb([10, ['Data length code: %d' % self.dlc, 'DLC: %d' % self.dlc, 'DLC']]) - self.last_databit = self.dlc_start + 3 + (self.dlc2len(self.dlc) * 8) + self.last_databit = self.dlc_start + 3 + (dlc2len(self.dlc) * 8) # Remember all databyte bits, except the very last one. elif bitnum in range(self.dlc_start + 4, self.last_databit): @@ -387,7 +396,7 @@ class Decoder(srd.Decoder): # The bits within a data byte are transferred MSB-first. elif bitnum == self.last_databit: self.ss_databytebits.append(self.samplenum) # Last databyte bit. - for i in range(self.dlc2len(self.dlc)): + for i in range(dlc2len(self.dlc)): x = self.dlc_start + 4 + (8 * i) b = int(''.join(str(d) for d in self.bits[x:x + 8]), 2) ss = self.ss_databytebits[i * 8] @@ -408,6 +417,12 @@ class Decoder(srd.Decoder): # Get the index of the current CAN frame bit (without stuff bits). bitnum = len(self.bits) - 1 + if self.fd and can_rx: + if bitnum == 16 and self.frame_type == 'standard' \ + or bitnum == 35 and self.frame_type == 'extended': + self.dom_edge_seen(force=True) + self.set_fast_bitrate() + # If this is a stuff bit, remove it from self.bits and ignore it. if self.is_stuff_bit(): self.putx([15, [str(can_rx)]]) @@ -483,4 +498,3 @@ class Decoder(srd.Decoder): self.dom_edge_seen() if self.matched[0]: self.handle_bit(can_rx) - self.bit_sampled()