##
## This file is part of the libsigrokdecode project.
##
-## Copyright (C) 2013 Uwe Hermann <uwe@hermann-uwe.de>
+## Copyright (C) 2013-2016 Uwe Hermann <uwe@hermann-uwe.de>
##
## This program is free software; you can redistribute it and/or modify
## it under the terms of the GNU General Public License as published by
## GNU General Public License for more details.
##
## You should have received a copy of the GNU General Public License
-## along with this program; if not, write to the Free Software
-## Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+## along with this program; if not, see <http://www.gnu.org/licenses/>.
##
import sigrokdecode as srd
+from common.srdhelper import bitpack
'''
OUTPUT_PYTHON format:
class ChannelError(Exception):
pass
+NUM_CHANNELS = 8
+
class Decoder(srd.Decoder):
- api_version = 2
+ api_version = 3
id = 'parallel'
name = 'Parallel'
longname = 'Parallel sync bus'
license = 'gplv2+'
inputs = ['logic']
outputs = ['parallel']
- optional_channels = channel_list(8)
+ optional_channels = channel_list(NUM_CHANNELS)
options = (
{'id': 'clock_edge', 'desc': 'Clock edge to sample on',
'default': 'rising', 'values': ('rising', 'falling')},
)
def __init__(self):
- self.oldclk = None
+ self.reset()
+
+ def reset(self):
self.items = []
- self.itemcount = 0
self.saved_item = None
- self.samplenum = 0
- self.oldpins = None
self.ss_item = self.es_item = None
self.first = True
def putw(self, data):
self.put(self.ss_word, self.es_word, self.out_ann, data)
- def handle_bits(self, datapins):
- # If this is the first item in a word, save its sample number.
- if self.itemcount == 0:
+ def handle_bits(self, item, used_pins):
+ # Save the item, and its sample number if it's the first part of a word.
+ if not self.items:
self.ss_word = self.samplenum
-
- # Get the bits for this item.
- item, used_pins = 0, datapins.count(b'\x01') + datapins.count(b'\x00')
- for i in range(used_pins):
- item |= datapins[i] << i
-
self.items.append(item)
- self.itemcount += 1
if self.first:
# Save the start sample and item for later (no output yet).
self.ss_item = self.samplenum
self.saved_item = item
- endian, ws = self.options['endianness'], self.options['wordsize']
-
# Get as many items as the configured wordsize says.
- if self.itemcount < ws:
+ ws = self.options['wordsize']
+ if len(self.items) < ws:
return
# Output annotations/python for a word (a collection of items).
+ # NOTE that this feature is currently not effective. The emission
+ # of Python annotations is commented out.
+ endian = self.options['endianness']
+ if endian == 'little':
+ self.items.reverse()
word = 0
for i in range(ws):
- if endian == 'little':
- word |= self.items[i] << ((ws - 1 - i) * used_pins)
- elif endian == 'big':
- word |= self.items[i] << (i * used_pins)
+ word |= self.items[i] << (i * used_pins)
self.es_word = self.samplenum
# self.putpw(['WORD', word])
# self.putw([1, ['%X' % word]])
self.ss_word = self.samplenum
- self.itemcount, self.items = 0, []
-
- def find_clk_edge(self, clk, datapins):
- # Ignore sample if the clock pin hasn't changed.
- if clk == self.oldclk:
- return
- self.oldclk = clk
-
- # Sample data on rising/falling clock edge (depends on config).
- c = self.options['clock_edge']
- if c == 'rising' and clk == 0: # Sample on rising clock edge.
- return
- elif c == 'falling' and clk == 1: # Sample on falling clock edge.
- return
-
- # Found the correct clock edge, now get the bits.
- self.handle_bits(datapins)
-
- def decode(self, ss, es, data):
- for (self.samplenum, pins) in data:
-
- # Ignore identical samples early on (for performance reasons).
- if self.oldpins == pins:
- continue
- self.oldpins = pins
-
- if sum(1 for p in pins if p in (0, 1)) == 0:
- raise ChannelError('At least one channel has to be supplied.')
+ self.items = []
- if pins[0] not in (0, 1):
- self.handle_bits(pins[1:])
- else:
- self.find_clk_edge(pins[0], pins[1:])
+ def decode(self):
+ # 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 = [
+ idx if self.has_channel(idx) else None
+ for idx in range(max_possible)
+ ]
+ 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)
+ idx_strip = max_connected + 1
+
+ # 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]
+
+ # 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]
+ bits = bits[1:idx_strip]
+ self.handle_bits(bitpack(bits), len(bits))
projects / libsigrokdecode.git / blobdiff