diff options
| -rw-r--r-- | configure.ac | 1 | ||||
| -rw-r--r-- | decoders/Makefile.am | 1 | ||||
| -rw-r--r-- | decoders/i2cdemux/__init__.py | 22 | ||||
| -rw-r--r-- | decoders/i2cdemux/i2cdemux.py | 90 |
4 files changed, 114 insertions, 0 deletions
diff --git a/configure.ac b/configure.ac index 7acdf40..6b19faa 100644 --- a/configure.ac +++ b/configure.ac @@ -154,6 +154,7 @@ AC_CONFIG_FILES([Makefile decoders/ddc/Makefile decoders/ebr30a_i2c_demux/Makefile decoders/i2c/Makefile + decoders/i2cdemux/Makefile decoders/mx25lxx05d/Makefile decoders/nunchuk/Makefile decoders/pan1321/Makefile diff --git a/decoders/Makefile.am b/decoders/Makefile.am index c1726cf..42888f9 100644 --- a/decoders/Makefile.am +++ b/decoders/Makefile.am @@ -24,6 +24,7 @@ SUBDIRS = \ ddc \ ebr30a_i2c_demux \ i2c \ + i2cdemux \ mx25lxx05d \ nunchuk \ pan1321 \ diff --git a/decoders/i2cdemux/__init__.py b/decoders/i2cdemux/__init__.py new file mode 100644 index 0000000..83f7b12 --- /dev/null +++ b/decoders/i2cdemux/__init__.py @@ -0,0 +1,22 @@ +## +## This file is part of the sigrok project. +## +## Copyright (C) 2012 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 +## the Free Software Foundation; either version 2 of the License, or +## (at your option) any later version. +## +## This program is distributed in the hope that it will be useful, +## but WITHOUT ANY WARRANTY; without even the implied warranty of +## MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +## 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 +## + +from .i2cdemux import * + diff --git a/decoders/i2cdemux/i2cdemux.py b/decoders/i2cdemux/i2cdemux.py new file mode 100644 index 0000000..ff597fe --- /dev/null +++ b/decoders/i2cdemux/i2cdemux.py @@ -0,0 +1,90 @@ +## +## This file is part of the sigrok project. +## +## Copyright (C) 2012 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 +## the Free Software Foundation; either version 2 of the License, or +## (at your option) any later version. +## +## This program is distributed in the hope that it will be useful, +## but WITHOUT ANY WARRANTY; without even the implied warranty of +## MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +## 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 +## + +# +# Generic I2C demultiplexing protocol decoder +# +# Takes an I2C stream as input and outputs multiple I2C streams, each stream +# containing only I2C packets for one specific I2C slave. +# + +import sigrokdecode as srd + +class Decoder(srd.Decoder): + api_version = 1 + id = 'i2cdemux' + name = 'I2C demux' + longname = 'Generic I2C demultiplexer' + desc = 'TODO.' + longdesc = 'TODO.' + license = 'gplv2+' + inputs = ['i2c'] + outputs = [] # TODO: Only known at run-time. + probes = [] + options = {} + annotations = [] + + def __init__(self, **kwargs): + self.packets = [] # Local cache of I2C packets + self.slaves = [] # List of known slave addresses + self.stream = -1 # Current output stream + self.streamcount = 0 # Number of created output streams + + def start(self, metadata): + self.out_proto = [] + + def report(self): + pass + + # Grab I2C packets into a local cache, until an I2C STOP condition + # packet comes along. At some point before that STOP condition, there + # will have been an ADDRESS READ or ADDRESS WRITE which contains the + # I2C address of the slave that the master wants to talk to. + # We use this slave address to figure out which output stream should + # get the whole chunk of packets (from START to STOP). + def decode(self, ss, es, data): + + cmd, databyte, ack = data + + # Add the I2C packet to our local cache. + self.packets += [[ss, es, data]] + + if cmd in ('ADDRESS READ', 'ADDRESS WRITE'): + if databyte in self.slaves: + self.stream = self.slaves.index(databyte) + return + + # We're never seen this slave, add a new stream. + self.slaves += [databyte] + self.out_proto += [self.add(srd.OUTPUT_PROTO, + 'i2c-%s' % hex(databyte))] + self.stream = self.streamcount + self.streamcount += 1 + elif cmd == 'STOP': + if self.stream == -1: + raise Exception('Invalid stream!') # FIXME? + + # Send the whole chunk of I2C packets to the correct stream. + for p in self.packets: + self.put(p[0], p[1], self.out_proto[self.stream], p[2]) + + self.packets = [] + self.stream = -1 + |