## ## This file is part of the sigrok project. ## ## Copyright (C) 2012 Iztok Jeras ## ## 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 # Annotation feed formats ANN_LINK = 0 ANN_NETWORK = 1 ANN_TRANSPORT = 2 # a dictionary of ROM commands and their names rom_command = {0x33: "READ ROM", 0x0f: "CONDITIONAL READ ROM", 0xcc: "SKIP ROM", 0x55: "MATCH ROM", 0xf0: "SEARCH ROM", 0xec: "CONDITIONAL SEARCH ROM", 0x3c: "OVERDRIVE SKIP ROM", 0x6d: "OVERDRIVE MATCH ROM"} class Decoder(srd.Decoder): api_version = 1 id = 'onewire' name = '1-Wire' longname = '1-Wire serial communication bus' desc = 'Bidirectional, half-duplex, asynchronous serial bus.' license = 'gplv2+' inputs = ['logic'] outputs = ['onewire'] probes = [ {'id': 'owr', 'name': 'OWR', 'desc': '1-Wire bus'}, ] optional_probes = [ {'id': 'pwr', 'name': 'PWR', 'desc': '1-Wire power'}, ] options = { 'overdrive' : ['Overdrive', 1], 'cnt_normal_bit' : ['Time (in samplerate periods) for normal mode sample bit' , 0], 'cnt_normal_presence' : ['Time (in samplerate periods) for normal mode sample presence', 0], 'cnt_normal_reset' : ['Time (in samplerate periods) for normal mode reset' , 0], 'cnt_overdrive_bit' : ['Time (in samplerate periods) for overdrive mode sample bit' , 0], 'cnt_overdrive_presence': ['Time (in samplerate periods) for overdrive mode sample presence', 0], 'cnt_overdrive_reset' : ['Time (in samplerate periods) for overdrive mode reset' , 0], } annotations = [ ['Link', 'Link layer events (reset, presence, bit slots)'], ['Network', 'Network layer events (device addressing)'], ['Transport', 'Transport layer events'], ] def __init__(self, **kwargs): # Common variables self.samplenum = 0 # Link layer variables self.lnk_state = 'WAIT FOR FALLING EDGE' self.lnk_event = 'NONE' self.lnk_present = 0 self.lnk_bit = 0 self.lnk_overdrive = 0 # Event timing variables self.lnk_fall = 0 self.lnk_rise = 0 self.net_beg = 0 self.net_end = 0 self.net_len = 0 # Network layer variables self.net_state = 'IDLE' self.net_cnt = 0 self.net_search = "P" self.net_data_p = 0x0 self.net_data_n = 0x0 self.net_data = 0x0 self.net_rom = 0x0000000000000000 def start(self, metadata): self.out_proto = self.add(srd.OUTPUT_PROTO, 'onewire') self.out_ann = self.add(srd.OUTPUT_ANN , 'onewire') # check if samplerate is appropriate self.samplerate = metadata['samplerate'] if (self.options['overdrive']): self.put(0, 0, self.out_ann, [ANN_LINK, ['NOTE: Sample rate checks assume overdrive mode.']]) if (self.samplerate < 2000000): self.put(0, 0, self.out_ann, [ANN_LINK, ['ERROR: Sampling rate is too low must be above 2MHz for proper overdrive mode decoding.']]) elif (self.samplerate < 5000000): self.put(0, 0, self.out_ann, [ANN_LINK, ['WARNING: Sampling rate is suggested to be above 5MHz for proper overdrive mode decoding.']]) else: self.put(0, 0, self.out_ann, [ANN_LINK, ['NOTE: Sample rate checks assume normal mode only.']]) if (self.samplerate < 400000): self.put(0, 0, self.out_ann, [ANN_LINK, ['ERROR: Sampling rate is too low must be above 400kHz for proper normal mode decoding.']]) elif (self.samplerate < 1000000): self.put(0, 0, self.out_ann, [ANN_LINK, ['WARNING: Sampling rate is suggested to be above 1MHz for proper normal mode decoding.']]) # The default 1-Wire time base is 30us, this is used to calculate sampling times. if (self.options['cnt_normal_bit']): self.cnt_normal_bit = self.options['cnt_normal_bit'] else: self.cnt_normal_bit = int(float(self.samplerate) * 0.000015) - 1 # 15ns if (self.options['cnt_normal_presence']): self.cnt_normal_presence = self.options['cnt_normal_presence'] else: self.cnt_normal_presence = int(float(self.samplerate) * 0.000075) - 1 # 75ns if (self.options['cnt_normal_reset']): self.cnt_normal_reset = self.options['cnt_normal_reset'] else: self.cnt_normal_reset = int(float(self.samplerate) * 0.000480) - 1 # 480ns if (self.options['cnt_overdrive_bit']): self.cnt_overdrive_bit = self.options['cnt_overdrive_bit'] else: self.cnt_overdrive_bit = int(float(self.samplerate) * 0.000002) - 1 # 2ns if (self.options['cnt_overdrive_presence']): self.cnt_overdrive_presence = self.options['cnt_overdrive_presence'] else: self.cnt_overdrive_presence = int(float(self.samplerate) * 0.000010) - 1 # 10ns if (self.options['cnt_overdrive_reset']): self.cnt_overdrive_reset = self.options['cnt_overdrive_reset'] else: self.cnt_overdrive_reset = int(float(self.samplerate) * 0.000048) - 1 # 48ns # calculating the slot size self.cnt_normal_slot = int(float(self.samplerate) * 0.000060) - 1 # 60ns self.cnt_overdrive_slot = int(float(self.samplerate) * 0.000006) - 1 # 6ns # organize values into lists self.cnt_bit = [self.cnt_normal_bit , self.cnt_overdrive_bit ] self.cnt_presence = [self.cnt_normal_presence, self.cnt_overdrive_presence] self.cnt_reset = [self.cnt_normal_reset , self.cnt_overdrive_reset ] self.cnt_slot = [self.cnt_normal_slot , self.cnt_overdrive_slot ] # Check if sample times are in the allowed range time_min = float(self.cnt_normal_bit ) / self.samplerate time_max = float(self.cnt_normal_bit+1) / self.samplerate if ( (time_min < 0.000005) or (time_max > 0.000015) ) : self.put(0, 0, self.out_ann, [ANN_LINK, ['WARNING: The normal mode data sample time interval (%2.1fus-%2.1fus) should be inside (5.0us, 15.0us).' % (time_min*1000000, time_max*1000000)]]) time_min = float(self.cnt_normal_presence ) / self.samplerate time_max = float(self.cnt_normal_presence+1) / self.samplerate if ( (time_min < 0.0000681) or (time_max > 0.000075) ) : self.put(0, 0, self.out_ann, [ANN_LINK, ['WARNING: The normal mode presence sample time interval (%2.1fus-%2.1fus) should be inside (68.1us, 75.0us).' % (time_min*1000000, time_max*1000000)]]) time_min = float(self.cnt_overdrive_bit ) / self.samplerate time_max = float(self.cnt_overdrive_bit+1) / self.samplerate if ( (time_min < 0.000001) or (time_max > 0.000002) ) : self.put(0, 0, self.out_ann, [ANN_LINK, ['WARNING: The overdrive mode data sample time interval (%2.1fus-%2.1fus) should be inside (1.0us, 2.0us).' % (time_min*1000000, time_max*1000000)]]) time_min = float(self.cnt_overdrive_presence ) / self.samplerate time_max = float(self.cnt_overdrive_presence+1) / self.samplerate if ( (time_min < 0.0000073) or (time_max > 0.000010) ) : self.put(0, 0, self.out_ann, [ANN_LINK, ['WARNING: The overdrive mode presence sample time interval (%2.1fus-%2.1fus) should be inside (7.3us, 10.0us).' % (time_min*1000000, time_max*1000000)]]) def report(self): pass def decode(self, ss, es, data): for (self.samplenum, (owr, pwr)) in data: # Data link layer # Clear events. self.lnk_event = "NONE" # State machine. if self.lnk_state == 'WAIT FOR FALLING EDGE': # The start of a cycle is a falling edge. if (owr == 0): # Save the sample number for the falling edge. self.lnk_fall = self.samplenum # Go to waiting for sample time self.lnk_state = 'WAIT FOR DATA SAMPLE' elif self.lnk_state == 'WAIT FOR DATA SAMPLE': # Sample data bit if (self.samplenum - self.lnk_fall == self.cnt_bit[self.lnk_overdrive]): self.lnk_bit = owr & 0x1 self.lnk_event = "DATA BIT" if (self.lnk_bit): self.lnk_state = 'WAIT FOR FALLING EDGE' else : self.lnk_state = 'WAIT FOR RISING EDGE' self.put(self.lnk_fall, self.cnt_bit[self.lnk_overdrive], self.out_ann, [ANN_LINK, ['BIT: %01x' % self.lnk_bit]]) elif self.lnk_state == 'WAIT FOR RISING EDGE': # The end of a cycle is a rising edge. if (owr == 1): # Check if this was a reset cycle if (self.samplenum - self.lnk_fall > self.cnt_normal_reset): # Save the sample number for the falling edge. self.lnk_rise = self.samplenum # Send a reset event to the next protocol layer. self.lnk_event = "RESET" self.lnk_state = "WAIT FOR PRESENCE DETECT" self.put(self.lnk_fall, self.lnk_rise, self.out_proto, ['RESET']) self.put(self.lnk_fall, self.lnk_rise, self.out_ann, [ANN_LINK , ['RESET']]) self.put(self.lnk_fall, self.lnk_rise, self.out_ann, [ANN_NETWORK , ['RESET']]) # Reset the timer. self.lnk_fall = self.samplenum elif ((self.samplenum - self.lnk_fall > self.cnt_overdrive_reset) and (self.lnk_overdrive)): # Save the sample number for the falling edge. self.lnk_rise = self.samplenum # Send a reset event to the next protocol layer. self.lnk_event = "RESET" self.lnk_state = "WAIT FOR PRESENCE DETECT" self.put(self.lnk_fall, self.lnk_rise, self.out_proto, ['RESET OVERDRIVE']) self.put(self.lnk_fall, self.lnk_rise, self.out_ann, [ANN_LINK , ['RESET OVERDRIVE']]) self.put(self.lnk_fall, self.lnk_rise, self.out_ann, [ANN_NETWORK , ['RESET OVERDRIVE']]) # Reset the timer. self.lnk_fall = self.samplenum # Otherwise this is assumed to be a data bit. else : self.lnk_state = "WAIT FOR FALLING EDGE" elif self.lnk_state == 'WAIT FOR PRESENCE DETECT': # Sample presence status if (self.samplenum - self.lnk_rise == self.cnt_presence[self.lnk_overdrive]): self.lnk_present = owr & 0x1 # Save the sample number for the falling edge. if not (self.lnk_present) : self.lnk_fall = self.samplenum # create presence detect event #self.lnk_event = "PRESENCE DETECT" if (self.lnk_present) : self.lnk_state = 'WAIT FOR FALLING EDGE' else : self.lnk_state = 'WAIT FOR RISING EDGE' present_str = "False" if self.lnk_present else "True" self.put(self.samplenum, 0, self.out_ann, [ANN_LINK , ['PRESENCE: ' + present_str]]) self.put(self.samplenum, 0, self.out_ann, [ANN_NETWORK, ['PRESENCE: ' + present_str]]) else: raise Exception('Invalid lnk_state: %d' % self.lnk_state) # Network layer # State machine. if (self.lnk_event == "RESET"): self.net_state = "COMMAND" self.net_search = "P" self.net_cnt = 0 elif (self.net_state == "IDLE"): pass elif (self.net_state == "COMMAND"): # Receiving and decoding a ROM command if (self.onewire_collect(8)): self.put(self.net_beg, self.net_len, self.out_ann, [ANN_NETWORK, ['ROM COMMAND: 0x%02x \'%s\'' % (self.net_data, rom_command[self.net_data])]]) if (self.net_data == 0x33): # READ ROM self.net_state = "GET ROM" elif (self.net_data == 0x0f): # CONDITIONAL READ ROM self.net_state = "GET ROM" elif (self.net_data == 0xcc): # SKIP ROM self.net_state = "TRANSPORT" elif (self.net_data == 0x55): # MATCH ROM self.net_state = "GET ROM" elif (self.net_data == 0xf0): # SEARCH ROM self.net_state = "SEARCH ROM" elif (self.net_data == 0xec): # CONDITIONAL SEARCH ROM self.net_state = "SEARCH ROM" elif (self.net_data == 0x3c): # OVERDRIVE SKIP ROM self.lnk_overdrive = 1 self.net_state = "TRANSPORT" elif (self.net_data == 0x69): # OVERDRIVE MATCH ROM self.lnk_overdrive = 1 self.net_state = "GET ROM" elif (self.net_state == "GET ROM"): # A 64 bit device address is selected # family code (1B) + serial number (6B) + CRC (1B) if (self.onewire_collect(64)): self.net_rom = self.net_data & 0xffffffffffffffff self.put(self.net_beg, self.net_len, self.out_ann, [ANN_NETWORK, ['ROM: 0x%016x' % self.net_rom]]) self.net_state = "TRANSPORT" elif (self.net_state == "SEARCH ROM"): # A 64 bit device address is searched for # family code (1B) + serial number (6B) + CRC (1B) if (self.onewire_search(64)): self.net_rom = self.net_data & 0xffffffffffffffff self.put(self.net_beg, self.net_len, self.out_ann, [ANN_NETWORK, ['ROM: 0x%016x' % self.net_rom]]) self.net_state = "TRANSPORT" elif (self.net_state == "TRANSPORT"): # The transport layer is handled in byte sized units if (self.onewire_collect(8)): self.put(self.net_beg, self.net_len, self.out_ann, [ANN_NETWORK , ['TRANSPORT: 0x%02x' % self.net_data]]) self.put(self.net_beg, self.net_len, self.out_ann, [ANN_TRANSPORT, ['TRANSPORT: 0x%02x' % self.net_data]]) self.put(self.net_beg, self.net_len, self.out_proto, ['transfer', self.net_data]) # TODO: Sending translort layer data to 1-Wire device models else: raise Exception('Invalid net_state: %s' % self.net_state) # Link/Network layer data collector def onewire_collect (self, length): if (self.lnk_event == "DATA BIT"): # Storing the sampe this sequence begins with if (self.net_cnt == 1): self.net_beg = self.lnk_fall self.net_data = self.net_data & ~(1 << self.net_cnt) | (self.lnk_bit << self.net_cnt) self.net_cnt = self.net_cnt + 1 # Storing the sampe this sequence ends with # In case the full length of the sequence is received, return 1 if (self.net_cnt == length): self.net_end = self.lnk_fall + self.cnt_slot[self.lnk_overdrive] self.net_len = self.net_end - self.net_beg self.net_data = self.net_data & ((1<