onewire: added transport layer decoder, it does not do much for now

1 files changed, 84 insertions, 0 deletions

diff --git a/decoders/onewire_transport/onewire_transport.py b/decoders/onewire_transport/onewire_transport.py
new file mode 100644
index 0000000..bc9efbb
--- /dev/null
+++ b/decoders/onewire_transport/onewire_transport.py
@@ -0,0 +1,84 @@
+##
+## This file is part of the sigrok project.
+##
+## Copyright (C) 2012 Iztok Jeras <iztok.jeras@gmail.com>
+##
+## 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
+##
+
+# 1-Wire protocol decoder
+
+import sigrokdecode as srd
+
+command = {0x44: "TEMPERATURE CONVERSION",
+           0xbe: "READ SCRATCHPAD"}
+
+class Decoder(srd.Decoder):
+    api_version = 1
+    id = 'onewire_transport'
+    name = '1-Wire transport layer'
+    longname = '1-Wire serial communication bus'
+    desc = 'Bidirectional, half-duplex, asynchronous serial bus.'
+    license = 'gplv2+'
+    inputs = ['onewire_network']
+    outputs = []
+    probes = []
+    optional_probes = []
+    options = {}
+    annotations = [
+        ['Transport', 'Transport layer events'],
+    ]
+
+    def __init__(self, **kwargs):
+        # Event timing variables
+        self.trn_beg = 0
+        self.trn_end = 0
+        # Transport layer variables
+        self.state   = 'ROM'
+        self.rom     = 0x0000000000000000
+
+    def start(self, metadata):
+        self.out_ann   = self.add(srd.OUTPUT_ANN  , 'onewire_transport')
+
+    def report(self):
+        pass
+
+    def decode(self, ss, es, data):
+        [code, val] = data
+
+        # State machine.
+        if (code == "RESET/PRESENCE"):
+            self.put(ss, es, self.out_ann, [0, ['RESET/PRESENCE: %s' % ('True' if val else 'False')]])
+            self.state = "ROM"
+        elif (code == "ROM"):
+            self.rom = val
+            self.put(ss, es, self.out_ann, [0, ['ROM: 0x%016x' % (val)]])
+            self.state = "COMMAND"
+        elif (code == "DATA"):
+            if (self.state == "COMMAND"):
+                    if (val in command):
+                        self.put(ss, es, self.out_ann, [0, ['FUNCTION COMMAND: 0x%02x \'%s\'' % (val, command[val])]])
+                        self.state = command[val]
+                    else:
+                        self.put(ss, es, self.out_ann, [0, ['FUNCTION COMMAND: 0x%02x \'%s\'' % (val, 'UNRECOGNIZED')]])
+                        self.state = "UNRECOGNIZED"
+            elif (self.state == "READ SCRATCHPAD"):
+                self.put(ss, es, self.out_ann, [0, ['SCRATCHPAD DATA: 0x%02x' % (val)]])
+            elif (self.state == "TEMPERATURE CONVERSION"):
+                self.put(ss, es, self.out_ann, [0, ['TEMPERATURE CONVERSION STATUS: 0x%02x' % (val)]])
+            elif (self.state == "UNRECOGNIZED"):
+                self.put(ss, es, self.out_ann, [0, ['UNRECOGNIZED: 0x%02x' % (val)]])
+            else:
+                raise Exception('Invalid state: %s' % self.state)