word <worditemcount> is 7, and so on.
'''
-def channel_list(num_channels):
- l = [{'id': 'clk', 'name': 'CLK', 'desc': 'Clock line'}]
- for i in range(num_channels):
- d = {'id': 'd%d' % i, 'name': 'D%d' % i, 'desc': 'Data line %d' % i}
- l.append(d)
- return tuple(l)
+NUM_CHANNELS = 8
+
+class Pin:
+ CLOCK = 0
+ DATA_0 = CLOCK + 1
+ DATA_N = DATA_0 + NUM_CHANNELS
+
+class Ann:
+ ITEM, WORD = range(2)
class ChannelError(Exception):
pass
-NUM_CHANNELS = 8
-
class Decoder(srd.Decoder):
api_version = 3
id = 'parallel'
inputs = ['logic']
outputs = ['parallel']
tags = ['Util']
- optional_channels = channel_list(NUM_CHANNELS)
+ optional_channels = tuple(
+ [{'id': 'clk', 'name': 'CLK', 'desc': 'Clock line'}] +
+ [
+ {'id': 'd%d' % i, 'name': 'D%d' % i, 'desc': 'Data line %d' % i}
+ for i in range(NUM_CHANNELS)
+ ]
+ )
options = (
{'id': 'clock_edge', 'desc': 'Clock edge to sample on',
- 'default': 'rising', 'values': ('rising', 'falling')},
+ 'default': 'rising', 'values': ('rising', 'falling', 'either')},
{'id': 'wordsize', 'desc': 'Data wordsize (# bus cycles)',
'default': 0},
{'id': 'endianness', 'desc': 'Data endianness',
'default': 'little', 'values': ('little', 'big')},
)
annotations = (
- ('items', 'Items'),
- ('words', 'Words'),
+ ('item', 'Item'),
+ ('word', 'Word'),
)
annotation_rows = (
- ('items', 'Items', (0,)),
- ('words', 'Words', (1,)),
+ ('items', 'Items', (Ann.ITEM,)),
+ ('words', 'Words', (Ann.WORD,)),
)
def __init__(self):
if self.saved_word is not None:
if self.options['wordsize'] > 0:
self.es_word = self.samplenum
- self.putw([1, [self.fmt_word.format(self.saved_word)]])
+ self.putw([Ann.WORD, [self.fmt_word.format(self.saved_word)]])
self.putpw(['WORD', self.saved_word])
self.saved_word = None
# Output the saved item (from the last CLK edge to the current).
self.es_item = self.samplenum
self.putpb(['ITEM', self.saved_item])
- self.putb([0, [self.fmt_item.format(self.saved_item)]])
+ self.putb([Ann.ITEM, [self.fmt_item.format(self.saved_item)]])
self.ss_item = self.samplenum
self.saved_item = item
# Determine which (optional) channels have input data. Insist in
# a non-empty input data set. Cope with sparse connection maps.
# Store enough state to later "compress" sampled input data.
- max_possible = len(self.optional_channels)
- idx_channels = [
+ data_indices = [
idx if self.has_channel(idx) else None
- for idx in range(max_possible)
+ for idx in range(Pin.DATA_0, Pin.DATA_N)
]
- has_channels = [idx for idx in idx_channels if idx is not None]
- if not has_channels:
- raise ChannelError('At least one channel has to be supplied.')
- max_connected = max(has_channels)
-
- # Determine .wait() conditions, depending on the presence of a
- # clock signal. Either inspect samples on the configured edge of
- # the clock, or inspect samples upon ANY edge of ANY of the pins
- # which provide input data.
- if self.has_channel(0):
- edge = self.options['clock_edge'][0]
- conds = {0: edge}
- else:
- conds = [{idx: 'e'} for idx in has_channels]
+ has_data = [idx for idx in data_indices if idx is not None]
+ if not has_data:
+ raise ChannelError('Need at least one data channel.')
+ max_connected = max(has_data)
# Pre-determine which input data to strip off, the width of
# individual items and multiplexed words, as well as format
# strings here. This simplifies call sites which run in tight
# loops later.
- idx_strip = max_connected + 1
- num_item_bits = idx_strip - 1
+ upper_data_bound = max_connected + 1
+ num_item_bits = upper_data_bound - Pin.DATA_0
num_word_items = self.options['wordsize']
num_word_bits = num_item_bits * num_word_items
- num_digits = (num_item_bits + 3) // 4
+ num_digits = (num_item_bits + 4 - 1) // 4
self.fmt_item = "{{:0{}x}}".format(num_digits)
- num_digits = (num_word_bits + 3) // 4
+ num_digits = (num_word_bits + 4 - 1) // 4
self.fmt_word = "{{:0{}x}}".format(num_digits)
+ # Determine .wait() conditions, depending on the presence of a
+ # clock signal. Either inspect samples on the configured edge of
+ # the clock, or inspect samples upon ANY edge of ANY of the pins
+ # which provide input data.
+ has_clock = self.has_channel(Pin.CLOCK)
+ if has_clock:
+ edge = {
+ 'rising': 'r',
+ 'falling': 'f',
+ 'either': 'e',
+ }.get(self.options['clock_edge'])
+ conds = [{Pin.CLOCK: edge}]
+ else:
+ conds = [{idx: 'e'} for idx in has_data]
+
# Keep processing the input stream. Assume "always zero" for
# not-connected input lines. Pass data bits (all inputs except
# clock) to the handle_bits() method.
while True:
pins = self.wait(conds)
- bits = [0 if idx is None else pins[idx] for idx in idx_channels]
- item = bitpack(bits[1:idx_strip])
+ data_bits = [0 if idx is None else pins[idx] for idx in data_indices]
+ data_bits = data_bits[:num_item_bits]
+ item = bitpack(data_bits)
self.handle_bits(item, num_item_bits)
projects / libsigrokdecode.git / blobdiff