srd: maxim_ds28ea00: Cosmetics, cleanups.

[libsigrokdecode.git] / decoders / maxim_ds28ea00 / maxim_ds28ea00.py

##
## This file is part of the sigrok project.
##
## Copyright (C) 2012 Iztok Jeras <iztok.jeras@gmail.com>
##
## 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
##

# Maxim DS28EA00 protocol decoder

import sigrokdecode as srd

# Dictionary of FUNCTION commands and their names.
command = {
    # Scratchpad
    0x4e: 'Write scratchpad',
    0xbe: 'Read scratchpad',
    0x48: 'Copy scratchpad',
    # Thermometer
    0x44: 'Convert temperature',
    0xb4: 'Read power mode',
    0xb8: 'Recall EEPROM',
    0xf5: 'PIO access read',
    0xA5: 'PIO access write',
    0x99: 'Chain',
}

class Decoder(srd.Decoder):
    api_version = 1
    id = 'maxim_ds28ea00'
    name = 'Maxim DS28EA00'
    longname = 'Maxim DS28EA00 1-Wire digital thermometer'
    desc = '1-Wire digital thermometer with Sequence Detect and PIO'
    license = 'gplv2+'
    inputs = ['onewire_network']
    outputs = ['maxim_ds28ea00']
    probes = []
    optional_probes = [
        {'id': 'pioa', 'name': 'PIOA/DONE#',
         'desc': 'PIOA channel and chain output'},
        {'id': 'piob', 'name': 'PIOB/EN#',
         'desc': 'PIOB channel and chain output'},
    ]
    options = {}
    annotations = [
        ['Text', 'Human-readable text'],
    ]

    def __init__(self, **kwargs):
        self.trn_beg = 0
        self.trn_end = 0
        self.state = 'ROM'
        self.rom = 0x0000000000000000

    def start(self, metadata):
        self.out_ann = self.add(srd.OUTPUT_ANN, 'maxim_ds28ea00')

    def report(self):
        pass

    def decode(self, ss, es, data):
        code, val = data

        # State machine.
        if code == 'RESET/PRESENCE':
            self.put(ss, es, self.out_ann,
                     [0, ['Reset/presence: %s' % ('true' if val else 'false')]])
            self.state = 'ROM'
        elif code == 'ROM':
            self.rom = val
            self.put(ss, es, self.out_ann, [0, ['ROM: 0x%016x' % (val)]])
            self.state = 'COMMAND'
        elif code == 'DATA':
            if self.state == 'COMMAND':
                if val in command:
                    self.put(ss, es, self.out_ann,
                             [0, ['Function command: 0x%02x \'%s\''
                             % (val, command[val])]])
                    self.state = command[val].upper()
                else:
                    self.put(ss, es, self.out_ann,
                             [0, ['Function command: 0x%02x \'%s\''
                             % (val, 'unrecognized')]])
                    self.state = 'UNRECOGNIZED'
            elif self.state == 'READ SCRATCHPAD':
                self.put(ss, es, self.out_ann,
                         [0, ['Scratchpad data: 0x%02x' % val]])
            elif self.state == 'CONVERT TEMPERATURE':
                self.put(ss, es, self.out_ann,
                         [0, ['Temperature conversion status: 0x%02x' % val]])
            elif self.state in [s.upper() for s in command.values()]:
                self.put(ss, es, self.out_ann,
                         [0, ['TODO \'%s\': 0x%02x' % (self.state, val)]])
            elif self.state == 'UNRECOGNIZED':
                self.put(ss, es, self.out_ann,
                         [0, ['Unrecognized command: 0x%02x' % val]])
            else:
                raise Exception('Invalid state: %s' % self.state)