From: Uwe Hermann Date: Thu, 19 Jul 2012 19:26:50 +0000 (+0200) Subject: srd: onewire_network: Cosmetics, simplifications, doc fixes. X-Git-Tag: libsigrokdecode-0.1.1~44 X-Git-Url: https://sigrok.org/gitaction?a=commitdiff_plain;h=6188e4e41ef0d9468a1b9f9bad5637ca862d73df;p=libsigrokdecode.git srd: onewire_network: Cosmetics, simplifications, doc fixes. --- diff --git a/decoders/onewire_network/__init__.py b/decoders/onewire_network/__init__.py index 9b6e510..25b3f5d 100644 --- a/decoders/onewire_network/__init__.py +++ b/decoders/onewire_network/__init__.py @@ -19,35 +19,44 @@ ## ''' -1-Wire protocol decoder. +1-Wire protocol decoder (network layer). -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) +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: -Network layer + - 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) + +Network layer: + +Protocol output format: +TODO. 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 COMMAND val name - The requested ROM command is displayed as an 8bit HEX value and by name. -- ROM val - The 64bit value of the addressed device is displayed: - family code (1B) + serial number (6B) + CRC (1B) -- DATA val - Data intended for the transport layer is displayed as an 8bit HEX value. + +The following 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 following network layer annotations are shown: + + - ROM command + The requested ROM command is displayed as an 8bit hex value and by name. + - ROM + The 64bit value of the addressed device is displayed: + Family code (1 byte) + serial number (6 bytes) + CRC (1 byte) + - Data + Data intended for the transport layer is displayed as an 8bit hex value. TODO: -- add CRC checks, to see if there were communication errors on the wire -- add reporting original/complement address values from the search algorithm + - Add CRC checks, to see if there were communication errors on the wire. + - Add reporting original/complement address values from the search algorithm. ''' from .onewire_network import * + diff --git a/decoders/onewire_network/onewire_network.py b/decoders/onewire_network/onewire_network.py index 9e641fd..a4f6f4a 100644 --- a/decoders/onewire_network/onewire_network.py +++ b/decoders/onewire_network/onewire_network.py @@ -18,27 +18,27 @@ ## Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA ## -# 1-Wire protocol decoder +# 1-Wire protocol decoder (network layer) import sigrokdecode as srd -# a dictionary of ROM commands and their names, next state +# Dictionary of ROM commands and their names, next state. command = { - 0x33: ["READ ROM" , "GET ROM" ], - 0x0f: ["CONDITIONAL READ ROM" , "GET ROM" ], - 0xcc: ["SKIP ROM" , "TRANSPORT" ], - 0x55: ["MATCH ROM" , "GET ROM" ], - 0xf0: ["SEARCH ROM" , "SEARCH ROM"], - 0xec: ["CONDITIONAL SEARCH ROM", "SEARCH ROM"], - 0x3c: ["OVERDRIVE SKIP ROM" , "TRANSPORT" ], - 0x6d: ["OVERDRIVE MATCH ROM" , "GET ROM" ] + 0x33: ['READ ROM' , 'GET ROM' ], + 0x0f: ['CONDITIONAL READ ROM' , 'GET ROM' ], + 0xcc: ['SKIP ROM' , 'TRANSPORT' ], + 0x55: ['MATCH ROM' , 'GET ROM' ], + 0xf0: ['SEARCH ROM' , 'SEARCH ROM'], + 0xec: ['CONDITIONAL SEARCH ROM', 'SEARCH ROM'], + 0x3c: ['OVERDRIVE SKIP ROM' , 'TRANSPORT' ], + 0x6d: ['OVERDRIVE MATCH ROM' , 'GET ROM' ], } class Decoder(srd.Decoder): api_version = 1 id = 'onewire_network' name = '1-Wire network layer' - longname = '1-Wire serial communication bus' + longname = '1-Wire serial communication bus (network layer)' desc = 'Bidirectional, half-duplex, asynchronous serial bus.' license = 'gplv2+' inputs = ['onewire_link'] @@ -55,116 +55,128 @@ class Decoder(srd.Decoder): self.net_beg = 0 self.net_end = 0 # Network layer variables - self.state = 'COMMAND' + self.state = 'COMMAND' self.bit_cnt = 0 - self.search = "P" - self.data_p = 0x0 - self.data_n = 0x0 - self.data = 0x0 + self.search = 'P' + self.data_p = 0x0 + self.data_n = 0x0 + self.data = 0x0 self.net_rom = 0x0000000000000000 def start(self, metadata): self.out_proto = self.add(srd.OUTPUT_PROTO, 'onewire_network') - self.out_ann = self.add(srd.OUTPUT_ANN , 'onewire_network') + self.out_ann = self.add(srd.OUTPUT_ANN, 'onewire_network') def report(self): pass + def putx(self, data): + # Helper function for most annotations. + self.put(self.net_beg, self.net_end, self.out_ann, data) + + def puty(self, data): + # Helper function for most protocol packets. + self.put(self.net_beg, self.net_end, self.out_proto, data) + def decode(self, ss, es, data): - [code, val] = data + code, val = data # State machine. - if (code == "RESET/PRESENCE"): - self.search = "P" + if code == 'RESET/PRESENCE': + self.search = 'P' self.bit_cnt = 0 - self.put(ss, es, self.out_ann, [0, ['RESET/PRESENCE: %s' % ('True' if val else 'False')]]) + self.put(ss, es, self.out_ann, + [0, ['RESET/PRESENCE: %s' % ('True' if val else 'False')]]) self.put(ss, es, self.out_proto, ['RESET/PRESENCE', val]) - self.state = "COMMAND" - elif (code == "BIT"): - if (self.state == "COMMAND"): - # Receiving and decoding a ROM command - if (self.onewire_collect(8, val, ss, es)): - if (self.data in command): - self.put(self.net_beg, self.net_end, self.out_ann, [0, - ['ROM COMMAND: 0x%02x \'%s\'' % (self.data, command[self.data][0])]]) + self.state = 'COMMAND' + elif code == 'BIT': + if self.state == 'COMMAND': + # Receiving and decoding a ROM command. + if self.onewire_collect(8, val, ss, es): + if self.data in command: + self.putx([0, ['ROM COMMAND: 0x%02x \'%s\'' + % (self.data, command[self.data][0])]]) self.state = command[self.data][1] else: - self.put(self.net_beg, self.net_end, self.out_ann, [0, - ['ROM COMMAND: 0x%02x \'%s\'' % (self.data, 'UNRECOGNIZED')]]) - self.state = "COMMAND ERROR" - elif (self.state == "GET ROM"): - # A 64 bit device address is selected - # family code (1B) + serial number (6B) + CRC (1B) - if (self.onewire_collect(64, val, ss, es)): + self.putx([0, ['ROM COMMAND: 0x%02x \'%s\'' + % (self.data, 'UNRECOGNIZED')]]) + self.state = 'COMMAND ERROR' + elif self.state == 'GET ROM': + # A 64 bit device address is selected. + # Family code (1B) + serial number (6B) + CRC (1B) + if self.onewire_collect(64, val, ss, es): self.net_rom = self.data & 0xffffffffffffffff - self.put(self.net_beg, self.net_end, self.out_ann, [0, ['ROM: 0x%016x' % self.net_rom]]) - self.put(self.net_beg, self.net_end, self.out_proto, ['ROM', self.net_rom]) - self.state = "TRANSPORT" - elif (self.state == "SEARCH ROM"): - # A 64 bit device address is searched for - # family code (1B) + serial number (6B) + CRC (1B) - if (self.onewire_search(64, val, ss, es)): + self.putx([0, ['ROM: 0x%016x' % self.net_rom]]) + self.puty(['ROM', self.net_rom]) + self.state = 'TRANSPORT' + elif self.state == 'SEARCH ROM': + # A 64 bit device address is searched for. + # Family code (1B) + serial number (6B) + CRC (1B) + if self.onewire_search(64, val, ss, es): self.net_rom = self.data & 0xffffffffffffffff - self.put(self.net_beg, self.net_end, self.out_ann, [0, ['ROM: 0x%016x' % self.net_rom]]) - self.put(self.net_beg, self.net_end, self.out_proto, ['ROM', self.net_rom]) - self.state = "TRANSPORT" - elif (self.state == "TRANSPORT"): - # The transport layer is handled in byte sized units - if (self.onewire_collect(8, val, ss, es)): - self.put(self.net_beg, self.net_end, self.out_ann, [0, ['DATA: 0x%02x' % self.data]]) - self.put(self.net_beg, self.net_end, self.out_proto, ['DATA', self.data]) - elif (self.state == "COMMAND ERROR"): - # Since the command is not recognized, print raw data - if (self.onewire_collect(8, val, ss, es)): - self.put(self.net_beg, self.net_end, self.out_ann, [0, ['ROM ERROR DATA: 0x%02x' % self.data]]) + self.putx([0, ['ROM: 0x%016x' % self.net_rom]]) + self.puty(['ROM', self.net_rom]) + self.state = 'TRANSPORT' + elif self.state == 'TRANSPORT': + # The transport layer is handled in byte sized units. + if self.onewire_collect(8, val, ss, es): + self.putx([0, ['DATA: 0x%02x' % self.data]]) + self.puty(['DATA', self.data]) + elif self.state == 'COMMAND ERROR': + # Since the command is not recognized, print raw data. + if self.onewire_collect(8, val, ss, es): + self.putx([0, ['ROM ERROR DATA: 0x%02x' % self.data]]) else: raise Exception('Invalid state: %s' % self.state) - - # Link/Network layer data collector - def onewire_collect (self, length, val, ss, es): - # Storing the sampe this sequence begins with - if (self.bit_cnt == 1): + # Link/Network layer data collector. + def onewire_collect(self, length, val, ss, es): + # Storing the sample this sequence begins with. + if self.bit_cnt == 1: self.net_beg = ss self.data = self.data & ~(1 << self.bit_cnt) | (val << self.bit_cnt) - self.bit_cnt = self.bit_cnt + 1 - # Storing the sampe this sequence ends with - # In case the full length of the sequence is received, return 1 - if (self.bit_cnt == length): - self.net_end = es - self.data = self.data & ((1<