diff options
Diffstat (limited to 'decoders')
| -rw-r--r-- | decoders/parallel/pd.py | 64 |
1 files changed, 32 insertions, 32 deletions
diff --git a/decoders/parallel/pd.py b/decoders/parallel/pd.py index dd356b4..10255f3 100644 --- a/decoders/parallel/pd.py +++ b/decoders/parallel/pd.py @@ -58,18 +58,12 @@ NUM_CHANNELS = 8 class Pin: CLOCK = 0 - DATA = range(1, NUM_CHANNELS + 1) + DATA_0 = CLOCK + 1 + DATA_N = DATA_0 + NUM_CHANNELS class Ann: ITEM, WORD = range(2) -def channel_list(): - 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) - class ChannelError(Exception): pass @@ -83,7 +77,13 @@ class Decoder(srd.Decoder): inputs = ['logic'] outputs = ['parallel'] tags = ['Util'] - optional_channels = channel_list() + 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')}, @@ -176,15 +176,27 @@ class Decoder(srd.Decoder): # 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) + 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. + 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 + 4 - 1) // 4 + self.fmt_item = "{{:0{}x}}".format(num_digits) + 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 @@ -195,26 +207,14 @@ class Decoder(srd.Decoder): edge = self.options['clock_edge'][0] conds = [{Pin.CLOCK: edge}] else: - conds = [{idx: 'e'} for idx in has_channels] - - # 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 - num_word_items = self.options['wordsize'] - num_word_bits = num_item_bits * num_word_items - num_digits = (num_item_bits + 3) // 4 - self.fmt_item = "{{:0{}x}}".format(num_digits) - num_digits = (num_word_bits + 3) // 4 - self.fmt_word = "{{:0{}x}}".format(num_digits) + 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[Pin.DATA[0]: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) |