ir_sirc: fixup decoder boilerplate

[libsigrokdecode.git] / decoders / ir_sirc / pd.py

##
## This file is part of the libsigrokdecode project.
##
## Copyright (C) 2020 Tom Flanagan <knio@zkpq.ca>
##
## 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, see <http://www.gnu.org/licenses/>.
##

import sigrokdecode as srd
from .lists import ADDRESSES

class SamplerateError(Exception):
    pass

class SIRCError(Exception):
    pass

class SIRCErrorSilent(SIRCError):
    pass

class Decoder(srd.Decoder):
    api_version = 3
    id = 'ir_sirc'
    name = 'IR SIRC'
    longname = 'Sony IR (SIRC)'
    desc = 'Sony infrared remote control protocol (SIRC).'
    license = 'gplv2+'
    tags = ['IR']
    inputs = ['logic']
    outputs = []
    channels = (
        {'id': 'ir', 'name': 'IR', 'desc': 'IR data line'},
    )
    options = (
        {'id': 'polarity', 'desc': 'Polarity', 'default': 'active-low',
            'values': ('active-low', 'active-high')},
    )
    annotations = (
        ('bit', 'Bit'),
        ('agc', 'AGC'),
        ('pause', 'Pause'),
        ('start', 'Start'),
        ('command', 'Command'),
        ('address', 'Address'),
        ('extended', 'Extended'),
        ('remote', 'Remote'),
        ('warning', 'Warning'),
    )
    annotation_rows = (
        ('bits', 'Bits', (0, 1, 2)),
        ('fields', 'Fields', (3, 4, 5, 6)),
        ('remotes', 'Remotes', (7,)),
        ('warnings', 'Warnings', (8,)),
    )

    def __init__(self):
        self.reset()

    def reset(self):
        pass

    def start(self):
        self.out_ann = self.register(srd.OUTPUT_ANN)
        self.active = self.options['polarity'] == 'active-high'

    def metadata(self, key, value):
        if key == srd.SRD_CONF_SAMPLERATE:
            self.samplerate = value

    def tolerance(self, start, end, expected):
        microseconds = 1000000 * (end - start) / self.samplerate
        tolerance = expected * 0.30
        return (expected - tolerance) < microseconds < (expected + tolerance)

    def wait(self, *conds, timeout=None):
        conds = list(conds)
        if timeout is not None:
            to = int(self.samplerate * timeout / 1000000)
            conds.append({'skip': to})
        start = self.samplenum
        signals = super(Decoder, self).wait(conds)
        end = self.samplenum
        return signals, start, end, self.matched

    def read_pulse(self, high, time):
        e = 'f' if high else 'r'
        max_time = int(time * 1.30)
        signals, start, end, (edge, timeout) = self.wait({0: e}, timeout=max_time)
        if timeout or not self.tolerance(start, end, time):
            raise SIRCError('Timeout')
        return signals, start, end, (edge, timeout)

    def read_bit(self):
        e = 'f' if self.active else 'r'
        signals, high_start, high_end, (edge, timeout) = self.wait({0:e}, timeout=2000)
        if timeout:
            raise SIRCError('Bit High Timeout')
        if self.tolerance(high_start, high_end, 1200):
            bit = 1
        elif self.tolerance(high_start, high_end, 600):
            bit = 0
        else:
            raise SIRCError('Bit Low Timeout')
        try:
            signals, low_start, low_end, matched = self.read_pulse(not self.active, 600)
            good = True
        except SIRCError:
            low_end = high_end + int(600 * self.samplerate / 1000000)
            good = False
        self.put(high_start, low_end, self.out_ann, [0, [str(bit)]])
        return bit, high_start, low_end, good

    def read_signal(self):
        # Start code
        try:
            signals, agc_start, agc_end, matched = self.read_pulse(self.active, 2400)
            signals, pause_start, pause_end, matched = self.read_pulse(not self.active, 600)
        except SIRCError:
            raise SIRCErrorSilent('not an SIRC message')
        self.put(agc_start, agc_end, self.out_ann, [1, ['AGC', 'A']])
        self.put(pause_start, pause_end, self.out_ann, [2, ['Pause', 'P']])
        self.put(agc_start, pause_end, self.out_ann, [3, ['Start', 'S']])

        # Read bits
        bits = []
        while True:
            bit, start, end, good = self.read_bit()
            bits.append((bit, start, end))
            if len(bits) > 20:
                raise SIRCError('too many bits')
            if not good:
                if len(bits) == 12:
                    command = bits[0:7]
                    address = bits[7:12]
                    extended = []
                elif len(bits) == 15:
                    command = bits[0:7]
                    address = bits[7:15]
                    extended = []
                elif len(bits) == 20:
                    command = bits[0:7]
                    address = bits[7:12]
                    extended = bits[12:20]
                else:
                    raise SIRCError('incorrect number of bits: {}'.format(len(bits)))
                break

        number = lambda bits:sum(b << i for i, (b, s, e) in enumerate(bits))
        command_num = number(command)
        address_num = number(address)
        command_str = '0x{:02X}'.format(command_num)
        address_str = '0x{:02X}'.format(address_num)
        self.put(command[0][1], command[-1][2], self.out_ann, [4, ['Command: ' + command_str, 'C:' + command_str]])
        self.put(address[0][1], address[-1][2], self.out_ann, [5, ['Address: ' + address_str, 'A:' + address_str]])
        extended_num = None
        if extended:
            extended_num = number(extended)
            extended_str = '0x{:02X}'.format(extended_num)
            self.put(extended[0][1], extended[-1][2], self.out_ann, [6, ['Extended: ' + extended_str, 'E:' + extended_str]])
        return address_num, command_num, extended_num, bits[0][1], bits[-1][2]

    def decode(self):
        if not self.samplerate:
            raise SamplerateError('Cannot decode without samplerate.')

        while True:
            e = 'h' if self.active else 'l'
            signal, start, end, matched = self.wait({0:e})
            try:
                address, command, extended, payload_start, payload_end = self.read_signal()
                names, commands = ADDRESSES.get((address, extended), (['Unknown Device: ', 'UNK: '], {}))
                text = commands.get(command, 'Unknown')
                self.put(end, payload_end, self.out_ann, [7, [n + text for n in names]])
            except SIRCErrorSilent as e:
                continue
            except SIRCError as e:
                self.put(end, self.samplenum, self.out_ann, [8, ['Error: ' + str(e), 'Error', 'E']])
                continue