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authorUwe Hermann <uwe@hermann-uwe.de>2012-07-21 20:37:41 +0200
committerUwe Hermann <uwe@hermann-uwe.de>2012-07-21 21:47:54 +0200
commit19dd61efcc1fe07c6a66f48f74b7926607f3a541 (patch)
tree4669d8fe41fde631107882af32cf615557c23dc7 /decoders/maxim_ds28ea00
parent5d7c5bcca4f770280cd4b58a8ea383fe97cf4a32 (diff)
downloadlibsigrokdecode-19dd61efcc1fe07c6a66f48f74b7926607f3a541.tar.gz
libsigrokdecode-19dd61efcc1fe07c6a66f48f74b7926607f3a541.zip
srd: Rename onewire_transport to maxim_ds28ea00.
It doesn't make sense to have one "generic" onewire_transport PD, as this layer is very much device-specific and such a generic PD would have to contain an accumulation of all possible features and commands and handling code of all existing (now and in the future) 1-Wire devices, which is neither possible nor useful nor elegant. There are (for example) 1-Wire thermometers, RTCs, EEPROMs, special-purpose security chips with passwords/keys, battery monitoring chips, and many many others. They all have a different set of features, commands and command codes, RAM areas/sizes/partitioning/contents, protocols, and so on. Thus, the layering for 1-Wire PD stacks should look like this: onewire_link -> onewire_network -> <specificdevice> Examples: onewire_link -> onewire_network -> maxim_ds28ea00 (special thermometer) onewire_link -> onewire_network -> maxim_ds2431 (1kbit EEPROM) onewire_link -> onewire_network -> maxim_ds2417 (RTC) onewire_link -> onewire_network -> maxim_ds2762 (battery monitor) onewire_link -> onewire_network -> maxim_ds1961s (SHA-1 eCash iButton) and so on... So, renaming onewire_transport to maxim_ds28ea00. The non-DS28EA00 specific code will be dropped and/or moved to other PDs on top of onewire_network later.
Diffstat (limited to 'decoders/maxim_ds28ea00')
-rw-r--r--decoders/maxim_ds28ea00/Makefile.am26
-rw-r--r--decoders/maxim_ds28ea00/__init__.py56
-rw-r--r--decoders/maxim_ds28ea00/maxim_ds28ea00.py105
3 files changed, 187 insertions, 0 deletions
diff --git a/decoders/maxim_ds28ea00/Makefile.am b/decoders/maxim_ds28ea00/Makefile.am
new file mode 100644
index 0000000..ee53993
--- /dev/null
+++ b/decoders/maxim_ds28ea00/Makefile.am
@@ -0,0 +1,26 @@
+##
+## 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
+##
+
+pkgdatadir = $(DECODERS_DIR)/maxim_ds28ea00
+
+dist_pkgdata_DATA = __init__.py maxim_ds28ea00.py
+
+CLEANFILES = *.pyc
+
diff --git a/decoders/maxim_ds28ea00/__init__.py b/decoders/maxim_ds28ea00/__init__.py
new file mode 100644
index 0000000..c6f063d
--- /dev/null
+++ b/decoders/maxim_ds28ea00/__init__.py
@@ -0,0 +1,56 @@
+##
+## 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
+##
+
+'''
+1-Wire protocol decoder.
+
+The 1-Wire protocol enables bidirectional communication over a single wire (and
+ground) between a single master and one or multiple slaves. The protocol is
+layered.
+- Link layer (reset, presence detection, reading/writing bits)
+- Network layer (skip/search/match device ROM addresses)
+- Transport layer (transport data between 1-Wire master and device)
+
+Transport layer
+
+The transport layer is the largest and most complex part of the protocol, since
+it is very device specific. The decoder is parsing only a small part of the
+protocol.
+
+Annotations:
+The next link layer annotations are shown:
+- RESET/PRESENCE True/False
+ The event is marked from the signal negative edge to the end of the reset
+ high period. It is also reported if there are any devices attached to the
+ bus.
+The next network layer annotations are shown:
+- ROM val
+ The 64bit value of the addressed device is displayed:
+ family code (1B) + serial number (6B) + CRC (1B)
+- FUNCTION COMMAND val name
+ The requested FUNCTION command is displayed as an 8bit HEX value and by name.
+- DATA val
+ Data intended for the transport layer is displayed as an 8bit HEX value.
+
+TODO:
+- add CRC checks for transport layer
+'''
+
+from .maxim_ds28ea00 import *
diff --git a/decoders/maxim_ds28ea00/maxim_ds28ea00.py b/decoders/maxim_ds28ea00/maxim_ds28ea00.py
new file mode 100644
index 0000000..96a5aab
--- /dev/null
+++ b/decoders/maxim_ds28ea00/maxim_ds28ea00.py
@@ -0,0 +1,105 @@
+##
+## 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
+
+# a dictionary of FUNCTION commands and their names
+command = {
+ # scratchpad
+ 0x4e: "WRITE SCRATCHPAD",
+ 0xbe: "READ SCRATCHPAD",
+ 0x48: "COPY SCRATCHPAD",
+ # thermometer
+ 0x44: "CONVERT TEMPERATURE",
+ 0xb4: "READ POWER MODE",
+ 0xb8: "RECALL EEPROM",
+ 0xf5: "PIO ACCESS READ",
+ 0xA5: "PIO ACCESS WRITE",
+ 0x99: "CHAIN",
+ # memory
+ 0xf0: "READ MEMORY",
+ 0xa5: "EXTENDED READ MEMORY",
+ 0x0f: "WRITE MEMORY",
+ 0x55: "WRITE STATUS",
+ 0xaa: "READ STATUS",
+ 0xf5: "CHANNEL ACCESS"
+}
+
+class Decoder(srd.Decoder):
+ api_version = 1
+ id = 'maxim_ds28ea00'
+ 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 == "CONVERT TEMPERATURE"):
+ self.put(ss, es, self.out_ann, [0, ['TEMPERATURE CONVERSION STATUS: 0x%02x' % (val)]])
+ elif (self.state in command.values()):
+ self.put(ss, es, self.out_ann, [0, ['TODO "%s": 0x%02x' % (self.state, val)]])
+ elif (self.state == "UNRECOGNIZED"):
+ self.put(ss, es, self.out_ann, [0, ['UNRECOGNIZED COMMAND: 0x%02x' % (val)]])
+ else:
+ raise Exception('Invalid state: %s' % self.state)