command. Slave addresses do not include bit 0 (the READ/WRITE indication bit).
For example, a slave address field could be 0x51 (instead of 0xa2).
For 'START', 'START REPEAT', 'STOP', 'ACK', and 'NACK' <pdata> is None.
+For 'BITS' <pdata> is a sequence of tuples of bit values and their start and
+stop positions, in LSB first order (although the I2C protocol is MSB first).
'''
-# CMD: [annotation-type-index, long annotation, short annotation]
+# Meaning of table items:
+# command -> [annotation class, annotation text in order of decreasing length]
proto = {
- 'START': [0, 'Start', 'S'],
- 'START REPEAT': [1, 'Start repeat', 'Sr'],
- 'STOP': [2, 'Stop', 'P'],
- 'ACK': [3, 'ACK', 'A'],
- 'NACK': [4, 'NACK', 'N'],
- 'BIT': [5, 'Bit', 'B'],
- 'ADDRESS READ': [6, 'Address read', 'AR'],
- 'ADDRESS WRITE': [7, 'Address write', 'AW'],
- 'DATA READ': [8, 'Data read', 'DR'],
- 'DATA WRITE': [9, 'Data write', 'DW'],
+ 'START': [0, 'Start', 'S'],
+ 'START REPEAT': [1, 'Start repeat', 'Sr'],
+ 'STOP': [2, 'Stop', 'P'],
+ 'ACK': [3, 'ACK', 'A'],
+ 'NACK': [4, 'NACK', 'N'],
+ 'BIT': [5, '{b:1d}'],
+ 'ADDRESS READ': [6, 'Address read: {b:02X}', 'AR: {b:02X}', '{b:02X}'],
+ 'ADDRESS WRITE': [7, 'Address write: {b:02X}', 'AW: {b:02X}', '{b:02X}'],
+ 'DATA READ': [8, 'Data read: {b:02X}', 'DR: {b:02X}', '{b:02X}'],
+ 'DATA WRITE': [9, 'Data write: {b:02X}', 'DW: {b:02X}', '{b:02X}'],
}
class Decoder(srd.Decoder):
def reset(self):
self.samplerate = None
- self.ss = self.es = self.ss_byte = -1
self.is_write = None
self.rem_addr_bytes = None
self.is_repeat_start = False
self.out_bitrate = self.register(srd.OUTPUT_META,
meta=(int, 'Bitrate', 'Bitrate from Start bit to Stop bit'))
- def putx(self, data):
- self.put(self.ss, self.es, self.out_ann, data)
+ def putg(self, ss, es, cls, text):
+ self.put(ss, es, self.out_ann, [cls, text])
- def putp(self, data):
- self.put(self.ss, self.es, self.out_python, data)
+ def putp(self, ss, es, data):
+ self.put(ss, es, self.out_python, data)
- def putb(self, data):
- self.put(self.ss, self.es, self.out_binary, data)
+ def putb(self, ss, es, data):
+ self.put(ss, es, self.out_binary, data)
def handle_start(self, pins):
- self.ss, self.es = self.samplenum, self.samplenum
- self.pdu_start = self.samplenum
- self.pdu_bits = 0
- cmd = 'START REPEAT' if self.is_repeat_start else 'START'
- self.putp([cmd, None])
- self.putx([proto[cmd][0], proto[cmd][1:]])
+ ss, es = self.samplenum, self.samplenum
+ if self.is_repeat_start:
+ cmd = 'START REPEAT'
+ else:
+ cmd = 'START'
+ self.pdu_start = self.samplenum
+ self.pdu_bits = 0
+ self.putp(ss, es, [cmd, None])
+ cls, texts = proto[cmd][0], proto[cmd][1:]
+ self.putg(ss, es, cls, texts)
self.state = 'FIND ADDRESS'
self.is_repeat_start = True
self.is_write = None
# bit's end sample number from the second last bit's width.
# (gsi: Shouldn't falling SCL be the end of the bit value?)
# Keep the bits in receive order (MSB first) during accumulation.
- if not self.data_bits:
- self.ss_byte = self.samplenum
if self.data_bits:
self.data_bits[-1][2] = self.samplenum
self.data_bits.append([sda, self.samplenum, self.samplenum])
cmd = 'DATA READ'
bin_class = 2
- self.ss, self.es = self.ss_byte, self.samplenum + self.bitwidth
+ ss_byte, es_byte = self.data_bits[0][1], self.data_bits[-1][2]
# Reverse the list of bits to LSB first order before emitting
# annotations and passing bits to upper layers. This may be
# unexpected because the protocol is MSB first, but it keeps
# backwards compatibility.
- self.data_bits.reverse()
- self.putp(['BITS', self.data_bits])
- self.putp([cmd, d])
+ lsb_bits = self.data_bits[:]
+ lsb_bits.reverse()
+ self.putp(ss_byte, es_byte, ['BITS', lsb_bits])
+ self.putp(ss_byte, es_byte, [cmd, d])
- self.putb([bin_class, bytes([d])])
+ self.putb(ss_byte, es_byte, [bin_class, bytes([d])])
- for bit in self.data_bits:
- self.put(bit[1], bit[2], self.out_ann, [5, ['%d' % bit[0]]])
+ for bit_value, ss_bit, es_bit in lsb_bits:
+ cls, texts = proto['BIT'][0], proto['BIT'][1:]
+ texts = [t.format(b = bit_value) for t in texts]
+ self.putg(ss_bit, es_bit, cls, texts)
if cmd.startswith('ADDRESS') and is_seven:
- self.ss, self.es = self.samplenum, self.samplenum + self.bitwidth
+ # Assign the last bit's location to the R/W annotation.
+ # Adjust the address value's location to the left.
+ ss_bit, es_bit = self.data_bits[-1][1], self.data_bits[-1][2]
+ es_byte = self.data_bits[-2][2]
+ cls = proto[cmd][0]
w = ['Write', 'Wr', 'W'] if self.is_write else ['Read', 'Rd', 'R']
- self.putx([proto[cmd][0], w])
- self.ss, self.es = self.ss_byte, self.samplenum
+ self.putg(ss_bit, es_bit, cls, w)
- self.putx([proto[cmd][0], ['%s: %02X' % (proto[cmd][1], d),
- '%s: %02X' % (proto[cmd][2], d), '%02X' % d]])
+ cls, texts = proto[cmd][0], proto[cmd][1:]
+ texts = [t.format(b = d) for t in texts]
+ self.putg(ss_byte, es_byte, cls, texts)
# Done with this packet.
self.data_bits.clear()
def get_ack(self, pins):
scl, sda = pins
- self.ss, self.es = self.samplenum, self.samplenum + self.bitwidth
+ # NOTE! Re-uses the last data bit's width for ACK/NAK as well.
+ # Which might be acceptable because this decoder implementation
+ # only gets to handle ACK/NAK after all DATA BITS were seen.
+ ss_bit, es_bit = self.samplenum, self.samplenum + self.bitwidth
cmd = 'NACK' if (sda == 1) else 'ACK'
- self.putp([cmd, None])
- self.putx([proto[cmd][0], proto[cmd][1:]])
+ self.putp(ss_bit, es_bit, [cmd, None])
+ cls, texts = proto[cmd][0], proto[cmd][1:]
+ self.putg(ss_bit, es_bit, cls, texts)
# Slave addresses can span one or two bytes, before data bytes
# follow. There can be an arbitrary number of data bytes. Stick
# with getting more address bytes if applicable, or enter or
def handle_stop(self, pins):
# Meta bitrate
- if self.samplerate:
- elapsed = 1 / float(self.samplerate) * (self.samplenum - self.pdu_start + 1)
+ if self.samplerate and self.pdu_start:
+ elapsed = self.samplenum - self.pdu_start + 1
+ elapsed /= self.samplerate
bitrate = int(1 / elapsed * self.pdu_bits)
- self.put(self.ss_byte, self.samplenum, self.out_bitrate, bitrate)
+ ss_meta, es_meta = self.pdu_start, self.samplenum
+ self.put(ss_meta, es_meta, self.out_bitrate, bitrate)
+ self.pdu_start = None
+ self.pdu_bits = 0
cmd = 'STOP'
- self.ss, self.es = self.samplenum, self.samplenum
- self.putp([cmd, None])
- self.putx([proto[cmd][0], proto[cmd][1:]])
+ ss, es = self.samplenum, self.samplenum
+ self.putp(ss, es, [cmd, None])
+ cls, texts = proto[cmd][0], proto[cmd][1:]
+ self.putg(ss, es, cls, texts)
self.state = 'FIND START'
self.is_repeat_start = False
self.is_write = None
projects / libsigrokdecode.git / blobdiff