##
## This file is part of the sigrok project.
##
## Copyright (C) 2011-2012 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
import sigrokdecode as srd
# Annotation feed formats
ANN_LINK = 0
ANN_NETWORK = 1
ANN_TRANSFER = 2
class Decoder(srd.Decoder):
api_version = 1
id = 'onewire'
name = '1-Wire'
longname = ''
desc = '1-Wire bus and MicroLan'
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', 0],
}
annotations = [
['Link', 'Link layer events (reset, presence, bit slots)'],
['Network', 'Network layer events (device addressing)'],
['Transfer', 'Transfer 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_fall = 0
self.lnk_present = 0
self.lnk_bit = 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
# Transport layer variables
self.trn_state = 'IDLE'
def start(self, metadata):
self.samplerate = metadata['samplerate']
self.out_proto = self.add(srd.OUTPUT_PROTO, 'onewire')
self.out_ann = self.add(srd.OUTPUT_ANN , 'onewire')
# The width of the 1-Wire time base (30us) in number of samples.
# TODO: optimize this value
self.time_base = float(self.samplerate) * float(0.000030)
self.put(self.lnk_fall, self.samplenum, self.out_ann, [ANN_LINK, ['time_base = %d' % self.time_base]])
def report(self):
pass
def decode(self, ss, es, data):
for (self.samplenum, (owr, pwr)) in data:
# print ("DEBUG: sample = %d, owr = %d, pwr = %d, lnk_fall = %d, lnk_state = %s" % (self.samplenum, owr, pwr, self.lnk_fall, self.lnk_state))
# 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':
# Data should be sample one 'time unit' after a falling edge
if (self.samplenum - self.lnk_fall == 0.5*self.time_base):
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.samplenum, 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):
# A reset cycle is longer than 8T.
if (self.samplenum - self.lnk_fall > 8*self.time_base):
# 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.samplenum, self.out_proto, ['RESET'])
self.put(self.lnk_fall, self.samplenum, self.out_ann, [ANN_LINK , ['RESET']])
self.put(self.lnk_fall, self.samplenum, self.out_ann, [ANN_NETWORK, ['RESET']])
# 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':
# Data should be sample one 'time unit' after a falling edge
if (self.samplenum - self.lnk_rise == 2.5*self.time_base):
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.lnk_fall, self.samplenum, self.out_ann, [ANN_LINK , ['PRESENCE: ' + present_str]])
self.put(self.lnk_fall, self.samplenum, 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"):
if (self.collect_data(8)):
# self.put(self.lnk_fall, self.samplenum,
# self.out_proto, ['ROM COMMAND', self.net_data])
self.put(self.lnk_fall, self.samplenum, self.out_ann, [ANN_NETWORK, ['ROM COMMAND: 0x%02x' % self.net_data]])
if (self.net_data == 0x33):
# READ ROM
self.put(self.lnk_fall, self.samplenum, self.out_ann, [ANN_NETWORK, ['ROM COMMAND: \'READ ROM\'']])
self.net_state = "GET ROM"
elif (self.net_data == 0x0f):
# READ ROM TODO
self.put(self.lnk_fall, self.samplenum, self.out_ann, [ANN_NETWORK, ['ROM COMMAND: \'READ ROM ???\'']])
self.net_state = "GET ROM"
elif (self.net_data == 0xcc):
# SKIP ROM
self.put(self.lnk_fall, self.samplenum, self.out_ann, [ANN_NETWORK, ['ROM COMMAND: \'SKIP ROM\'']])
self.net_state = "IDLE"
self.trn_state = "COMMAND"
elif (self.net_data == 0x55):
# MATCH ROM
self.put(self.lnk_fall, self.samplenum, self.out_ann, [ANN_NETWORK, ['ROM COMMAND: \'MATCH ROM\'']])
self.net_state = "GET ROM"
elif (self.net_data == 0xf0):
# SEARCH ROM
self.put(self.lnk_fall, self.samplenum, self.out_ann, [ANN_NETWORK, ['ROM COMMAND: \'SEARCH ROM\'']])
self.net_state = "SEARCH ROM"
elif (self.net_data == 0x3c):
# OVERDRIVE SKIP ROM
self.put(self.lnk_fall, self.samplenum, self.out_ann, [ANN_NETWORK, ['ROM COMMAND: \'OVERDRIVE SKIP ROM\'']])
self.net_state = "IDLE"
self.trn_state = "COMMAND"
elif (self.net_data == 0x69):
# OVERDRIVE MATCH ROM
self.put(self.lnk_fall, self.samplenum, self.out_ann, [ANN_NETWORK, ['ROM COMMAND: \'OVERDRIVE MATCH ROM\'']])
self.net_state = "GET ROM"
elif (self.net_state == "GET ROM"):
# family code (1B) + serial number (6B) + CRC (1B)
if (self.collect_data((1+6+1)*8)):
self.net_rom = self.net_data & 0xffffffffffffffff
self.put(self.lnk_fall, self.samplenum, self.out_ann, [ANN_NETWORK, ['ROM: 0x%016x' % self.net_rom]])
self.net_state = "IDLE"
self.trn_state = "COMMAND"
elif (self.net_state == "SEARCH ROM"):
# family code (1B) + serial number (6B) + CRC (1B)
if (self.collect_search((1+6+1)*8)):
self.net_rom = self.net_data & 0xffffffffffffffff
self.put(self.lnk_fall, self.samplenum, self.out_ann, [ANN_NETWORK, ['ROM: 0x%016x' % self.net_rom]])
self.net_state = "IDLE"
self.trn_state = "COMMAND"
else:
raise Exception('Invalid net_state: %s' % self.net_state)
# Transport layer
# State machine.
if (self.lnk_event == "RESET"):
self.trn_state = "IDLE"
elif (self.trn_state == "IDLE"):
pass
elif (self.trn_state == "COMMAND"):
if (self.collect_data(8)):
# self.put(self.lnk_fall, self.samplenum, self.out_proto, ['FUNCTION COMMAND', self.net_data])
self.put(self.lnk_fall, self.samplenum, self.out_ann, [ANN_NETWORK , ['FUNCTION COMMAND: 0x%02x' % self.net_data]])
self.put(self.lnk_fall, self.samplenum, self.out_ann, [ANN_TRANSFER, ['FUNCTION COMMAND: 0x%02x' % self.net_data]])
if (self.net_data == 0x48):
# COPY SCRATCHPAD
self.trn_state = "TODO"
elif (self.net_data == 0x4e):
# WRITE SCRATCHPAD
self.trn_state = "TODO"
elif (self.net_data == 0xbe):
# READ SCRATCHPAD
self.trn_state = "TODO"
elif (self.net_data == 0xb8):
# RECALL E2
self.trn_state = "TODO"
elif (self.net_data == 0xb4):
# READ POWER SUPPLY
self.trn_state = "TODO"
else:
# unsupported commands
self.trn_state = "TODO"
elif (self.trn_state == "TODO"):
# self.put(self.lnk_fall, self.samplenum, self.out_ann, [ANN_NETWORK , ['TODO unsupported transfer state: %s' % self.trn_state]])
# self.put(self.lnk_fall, self.samplenum, self.out_ann, [ANN_TRANSFER, ['TODO unsupported transfer state: %s' % self.trn_state]])
pass
else:
raise Exception('Invalid trn_state: %s' % self.trn_state)
# Link/Network layer data collector
def collect_data (self, length):
if (self.lnk_event == "DATA BIT"):
#print ("DEBUG: BIT=%d t0=%d t+=%d" % (self.lnk_bit, self.lnk_fall, self.samplenum))
self.net_data = self.net_data & ~(1 << self.net_cnt) | (self.lnk_bit << self.net_cnt)
self.net_cnt = self.net_cnt + 1
if (self.net_cnt == length):
self.net_data = self.net_data & ((1<<length)-1)
self.net_cnt = 0
return (1)
else:
return (0)
else:
return (0)
# Link/Network layer search collector
def collect_search (self, length):
if (self.lnk_event == "DATA BIT"):
#print ("DEBUG: SEARCH=%s BIT=%d t0=%d t+=%d" % (self.net_search, self.lnk_bit, self.lnk_fall, self.samplenum))
if (self.net_search == "P"):
self.net_data_p = self.net_data_p & ~(1 << self.net_cnt) | (self.lnk_bit << self.net_cnt)
self.net_search = "N"
elif (self.net_search == "N"):
self.net_data_n = self.net_data_n & ~(1 << self.net_cnt) | (self.lnk_bit << self.net_cnt)
self.net_search = "D"
elif (self.net_search == "D"):
self.net_data = self.net_data & ~(1 << self.net_cnt) | (self.lnk_bit << self.net_cnt)
self.net_search = "P"
self.net_cnt = self.net_cnt + 1
if (self.net_cnt == length):
self.net_data_p = self.net_data_p & ((1<<length)-1)
self.net_data_n = self.net_data_n & ((1<<length)-1)
self.net_data = self.net_data & ((1<<length)-1)
self.net_search = "P"
self.net_cnt = 0
return (1)
else:
return (0)
else:
return (0)