diff options
Diffstat (limited to 'decoders/onewire/onewire.py')
| -rw-r--r-- | decoders/onewire/onewire.py | 104 |
1 files changed, 68 insertions, 36 deletions
diff --git a/decoders/onewire/onewire.py b/decoders/onewire/onewire.py index 24d265b..ec1cc8d 100644 --- a/decoders/onewire/onewire.py +++ b/decoders/onewire/onewire.py @@ -64,11 +64,14 @@ class Decoder(srd.Decoder): self.lnk_fall = 0 self.lnk_present = 0 self.lnk_bit = 0 + self.lnk_cnt = 0 + self.lnk_byte = 0x00 # Network layer variables + self.net_mode = 'WRITE' self.net_state = 'WAIT FOR COMMAND' self.net_event = 'NONE' self.net_cnt = 0 - self.net_cmd = 0 + self.net_cmd = 0x00 # Transport layer variables self.trn_state = 'WAIT FOR EVENT' self.trn_event = 'NONE' @@ -104,7 +107,6 @@ class Decoder(srd.Decoder): self.lnk_state = 'WAIT FOR DATA SAMPLE' self.put(self.lnk_fall, self.samplenum, self.out_ann, [ANN_DEC, ['LNK: NEGEDGE: ']]) - print ("DEBUG: NEGEDGE t0=%d t+=%d" % (self.lnk_fall, self.samplenum)) 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 == 1*self.time_base): @@ -114,7 +116,6 @@ class Decoder(srd.Decoder): else : self.lnk_state = 'WAIT FOR RISING EDGE' self.put(self.lnk_fall, self.samplenum, self.out_ann, [ANN_DEC, ['LNK: BIT: ' + str(self.lnk_bit)]]) - print ("DEBUG: BIT=%d t0=%d t+=%d" % (self.lnk_bit, self.lnk_fall, self.samplenum)) elif self.lnk_state == 'WAIT FOR RISING EDGE': # The end of a cycle is a rising edge. if (owr == 1): @@ -139,15 +140,46 @@ class Decoder(srd.Decoder): # 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_bit) : self.lnk_state = 'WAIT FOR FALLING EDGE' - else : self.lnk_state = 'WAIT FOR RISING EDGE' + if (self.lnk_present) : 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_DEC, ['LNK: PRESENCE: ' + str(self.lnk_present)]]) print ("DEBUG: PRESENCE=%d t0=%d t+=%d" % (self.lnk_present, self.lnk_fall, self.samplenum)) else: raise Exception('Invalid lnk_state: %d' % self.lnk_state) + # Link layer (byte sized units) + + # State machine. + if (self.lnk_event == "RESET"): + self.lnk_cnt = 0 + self.lnk_byte = 0x00 + elif (self.lnk_event == "DATA BIT"): + if (self.net_mode in ["WRITE", "READ"]): + self.lnk_cnt = self.lnk_cnt + 1 + self.lnk_byte = (self.lnk_byte << 1) | self.lnk_bit + if (self.lnk_cnt == 8): + print ("DEBUG: BYTE=0x%02x t0=%d t+=%d" % (self.lnk_byte, self.lnk_fall, self.samplenum)) + self.lnk_event = "DATA BYTE" + self.lnk_cnt = 0 + self.lnk_byte = 0x00 + elif (self.net_mode == "SEARCH"): + self.lnk_cnt = self.lnk_cnt + 1 + self.lnk_byte = (self.lnk_byte << 1) | self.lnk_bit + if (self.lnk_cnt == 8): + print ("DEBUG: BYTE=0x%02x t0=%d t+=%d" % (self.lnk_byte, self.lnk_fall, self.samplenum)) + self.lnk_event = "DATA BYTE" + self.lnk_cnt = 0 + self.lnk_byte = 0x00 + else: + raise Exception('Invalid net_mode: %s' % self.net_mode) + elif not (self.lnk_event == "NONE"): + raise Exception('Invalid lnk_event: %s' % self.lnk_event) + # Network layer # Clear events. @@ -156,41 +188,41 @@ class Decoder(srd.Decoder): if (self.lnk_event == "RESET"): self.net_state = "WAIT FOR COMMAND" self.net_cnt = 0 - self.net_cmd = 0 elif (self.lnk_event == "DATA BIT"): + pass + elif (self.lnk_event == "DATA BYTE"): if (self.net_state == "WAIT FOR COMMAND"): - self.net_cnt = self.net_cnt + 1 - self.net_cmd = (self.net_cmd << 1) & self.lnk_bit - if (self.net_cnt == 8): - self.put(self.lnk_fall, self.samplenum, - self.out_proto, ['LNK: COMMAND', self.net_cmd]) - self.put(self.lnk_fall, self.samplenum, self.out_ann, - [ANN_DEC, ['LNK: COMMAND: ' + self.net_cmd]]) - if (self.net_cmd == 0x33): - # READ ROM - break - elif (self.net_cmd == 0x0f): - # READ ROM - break - elif (self.net_cmd == 0xcc): - # SKIP ROM - break - elif (self.net_cmd == 0x55): - # MATCH ROM - break - elif (self.net_cmd == 0xf0): - # SEARCH ROM - break - elif (self.net_cmd == 0x3c): - # OVERDRIVE SKIP ROM - break - elif (self.net_cmd == 0x69): - # OVERDRIVE MATCH ROM - break - self.net_cnt = 0 + self.net_cmd = self.lnk_byte +# self.put(self.lnk_fall, self.samplenum, +# self.out_proto, ['LNK: COMMAND', self.net_cmd]) + self.put(self.lnk_fall, self.samplenum, self.out_ann, + [ANN_DEC, ['LNK: COMMAND: 0x' + hex(self.net_cmd)]]) + print ("DEBUG: CMD=0x%02x t0=%d t+=%d" % (self.net_cmd, self.lnk_fall, self.samplenum)) + if (self.net_cmd == 0x33): + # READ ROM + pass + elif (self.net_cmd == 0x0f): + # READ ROM + pass + elif (self.net_cmd == 0xcc): + # SKIP ROM + pass + elif (self.net_cmd == 0x55): + # MATCH ROM + pass + elif (self.net_cmd == 0xf0): + # SEARCH ROM + pass + elif (self.net_cmd == 0x3c): + # OVERDRIVE SKIP ROM + pass + elif (self.net_cmd == 0x69): + # OVERDRIVE MATCH ROM + pass + self.net_cnt = 0 elif (self.net_state == "WAIT FOR ROM"): # - break + pass else: raise Exception('Invalid net_state: %d' % self.net_state) elif not (self.lnk_event == "NONE"): |