diff options
Diffstat (limited to 'decoders/i2c.py')
| -rw-r--r-- | decoders/i2c.py | 124 |
1 files changed, 65 insertions, 59 deletions
diff --git a/decoders/i2c.py b/decoders/i2c.py index 1c4903b..0f554f7 100644 --- a/decoders/i2c.py +++ b/decoders/i2c.py @@ -89,26 +89,9 @@ # 'data': (actual data as integer ???) TODO: This can be very variable... # 'ann': (string; additional annotations / comments) # -# Example output: -# [{'type': 'S', 'range': (150, 160), 'data': None, 'ann': 'Foobar'}, -# {'type': 'AW', 'range': (200, 300), 'data': 0x50, 'ann': 'Slave 4'}, -# {'type': 'DW', 'range': (310, 370), 'data': 0x00, 'ann': 'Init cmd'}, -# {'type': 'AR', 'range': (500, 560), 'data': 0x50, 'ann': 'Get stat'}, -# {'type': 'DR', 'range': (580, 640), 'data': 0xfe, 'ann': 'OK'}, -# {'type': 'P', 'range': (650, 660), 'data': None, 'ann': None}] -# -# Possible other events: -# - Error event in case protocol looks broken: -# [{'type': 'ERROR', 'range': (min, max), -# 'data': TODO, 'ann': 'This is not a Microchip 24XX64 EEPROM'}, -# [{'type': 'ERROR', 'range': (min, max), -# 'data': TODO, 'ann': 'TODO'}, -# - TODO: Make list of possible errors accessible as metadata? -# # TODO: I2C address of slaves. # TODO: Handle multiple different I2C devices on same bus # -> we need to decode multiple protocols at the same time. -# TODO: range: Always contiguous? Splitted ranges? Multiple per event? # # @@ -128,22 +111,31 @@ import sigrokdecode -# symbols for i2c decoders up the stack -START = 1 -START_REPEAT = 2 -STOP = 3 -ACK = 4 -NACK = 5 -ADDRESS_READ = 6 -ADDRESS_WRITE = 7 -DATA_READ = 8 -DATA_WRITE = 9 +# values are verbose and short annotation, respectively +protocol = { + 'START': ['START', 'S'], + 'START_REPEAT': ['START REPEAT', 'Sr'], + 'STOP': ['STOP', 'P'], + 'ACK': ['ACK', 'A'], + 'NACK': ['NACK', 'N'], + 'ADDRESS_READ': ['ADDRESS READ', 'AR'], + 'ADDRESS_WRITE': ['ADDRESS WRITE','AW'], + 'DATA_READ': ['DATA READ', 'DR'], + 'DATA_WRITE': ['DATA WRITE', 'DW'], +} +# export protocol keys as symbols for i2c decoders up the stack +EXPORT = [ protocol.keys() ] # States FIND_START = 0 FIND_ADDRESS = 1 FIND_DATA = 2 +# annotation feed formats +ANN_SHIFTED = 0 +ANN_SHIFTED_SHORT = 1 +ANN_RAW = 2 + class Decoder(sigrokdecode.Decoder): id = 'i2c' @@ -163,6 +155,16 @@ class Decoder(sigrokdecode.Decoder): options = { 'address-space': ['Address space (in bits)', 7], } + annotation = [ + # ANN_SHIFTED + ["7-bit shifted hex", + "Read/Write bit shifted out from the 8-bit i2c slave address"], + # ANN_SHIFTED_SHORT + ["7-bit shifted hex (short)", + "Read/Write bit shifted out from the 8-bit i2c slave address"], + # ANN_RAW + ["Raw hex", "Unaltered raw data"] + ] def __init__(self, **kwargs): self.output_protocol = None @@ -178,8 +180,8 @@ class Decoder(sigrokdecode.Decoder): self.oldsda = None def start(self, metadata): - self.output_protocol = self.output_new(2) - self.output_annotation = self.output_new(1) + self.output_protocol = self.output_new(1) + self.output_annotation = self.output_new(0) def report(self): pass @@ -204,13 +206,12 @@ class Decoder(sigrokdecode.Decoder): def found_start(self, scl, sda): if self.is_repeat_start == 1: - out_proto = [ START_REPEAT ] - out_ann = [ "START REPEAT" ] + cmd = 'START_REPEAT' else: - out_proto = [ START ] - out_ann = [ "START" ] - self.put(self.output_protocol, out_proto) - self.put(self.output_annotation, out_ann) + cmd = 'START' + self.put(self.output_protocol, [ cmd ]) + self.put(self.output_annotation, [ ANN_SHIFTED, [protocol[cmd][0]] ]) + self.put(self.output_annotation, [ ANN_SHIFTED_SHORT, [protocol[cmd][1]] ]) self.state = FIND_ADDRESS self.bitcount = self.databyte = 0 @@ -233,6 +234,10 @@ class Decoder(sigrokdecode.Decoder): if self.bitcount != 9: return [] + # send raw output annotation before we start shifting out + # read/write and ack/nack bits + self.put(self.output_annotation, [ANN_RAW, ["0x%.2x" % self.databyte]]) + # We received 8 address/data bits and the ACK/NACK bit. self.databyte >>= 1 # Shift out unwanted ACK/NACK bit here. @@ -246,33 +251,32 @@ class Decoder(sigrokdecode.Decoder): # TODO: Error? pass - out_proto = [] - out_ann = [] + # last bit that came in was the ACK/NACK bit (1 = NACK) + if sda == 1: + ack_bit = 'NACK' + else: + ack_bit = 'ACK' + # TODO: Simplify. if self.state == FIND_ADDRESS and self.wr == 1: - cmd = ADDRESS_WRITE - ann = 'ADDRESS WRITE' + cmd = 'ADDRESS_WRITE' elif self.state == FIND_ADDRESS and self.wr == 0: - cmd = ADDRESS_READ - ann = 'ADDRESS READ' + cmd = 'ADDRESS_READ' elif self.state == FIND_DATA and self.wr == 1: - cmd = DATA_WRITE - ann = 'DATA WRITE' + cmd = 'DATA_WRITE' elif self.state == FIND_DATA and self.wr == 0: - cmd = DATA_READ - ann = 'DATA READ' - out_proto.append( [cmd, d] ) - out_ann.append( ["%s" % ann, "0x%02x" % d] ) - - if sda == 1: - out_proto.append( [NACK] ) - out_ann.append( ["NACK"] ) - else: - out_proto.append( [ACK] ) - out_ann.append( ["ACK"] ) - - self.put(self.output_protocol, out_proto) - self.put(self.output_annotation, out_ann) + cmd = 'DATA_READ' + self.put(self.output_protocol, [ [cmd, d], [ack_bit] ] ) + self.put(self.output_annotation, [ANN_SHIFTED, [ + "%s" % protocol[cmd][0], + "0x%02x" % d, + "%s" % protocol[ack_bit][0]] + ] ) + self.put(self.output_annotation, [ANN_SHIFTED_SHORT, [ + "%s" % protocol[cmd][1], + "0x%02x" % d, + "%s" % protocol[ack_bit][1]] + ] ) self.bitcount = self.databyte = 0 self.startsample = -1 @@ -285,8 +289,9 @@ class Decoder(sigrokdecode.Decoder): pass def found_stop(self, scl, sda): - self.put(self.output_protocol, [ STOP ]) - self.put(self.output_annotation, [ "STOP" ]) + self.put(self.output_protocol, [ 'STOP' ]) + self.put(self.output_annotation, [ ANN_SHIFTED, [protocol['STOP'][0]] ]) + self.put(self.output_annotation, [ ANN_SHIFTED_SHORT, [protocol['STOP'][1]] ]) self.state = FIND_START self.is_repeat_start = 0 @@ -294,6 +299,7 @@ class Decoder(sigrokdecode.Decoder): def put(self, output_id, data): # inject sample range into the call up to sigrok + # TODO: 0-0 sample range for now super(Decoder, self).put(0, 0, output_id, data) def decode(self, timeoffset, duration, data): |