pd.py

##
## This file is part of the libsigrokdecode project.
##
## Copyright (C) 2022 Matej Martinček <matomarss@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, see <http://www.gnu.org/licenses/>.
##

'''
OUTPUT_PYTHON format:

Packet:
[<ptype>, <pdata>]

<ptype>:
 - 'ADDRESS
 - 'DATA'

<pdata> is the data value associated with the 'DATA'
command.
'''

import re
import sigrokdecode as srd
from common.srdhelper import bcd2int, SrdIntEnum

class Decoder(srd.Decoder):
    api_version = 3
    id = 'uart_extractor'
    name = 'UART bytes extractor'
    longname = 'The UART bytes extractor'
    desc = 'Extracts data packets values from UART communication and potentially sends them to other stack-decoders'
    license = 'gplv2+'
    inputs = ['uart']
    outputs = ['dataBytes']
    tags = ['Embedded/industrial']
    annotations = ()
    annotation_rows = ()

    def __init__(self):
        self.reset()

    def reset(self):
        self.state = 'INACTIVE'

    def start(self):
        self.out_python = self.register(srd.OUTPUT_PYTHON)

    def putp(self, data):
        self.put(self.ss, self.es, self.out_python, data)

    def send_data_value(self, b, rxtx):
        # Send the value of the received data of type DATA onto row no. rxtx
        self.putp(['DATA', b, rxtx])

    def decode(self, ss, es, data):
        cmd, rxtx, data_value_and_bits = data

        # Store the start/end samples of this packet.
        self.ss, self.es = ss, es

        # State machine.
        if cmd == 'STARTBIT':
            self.state = 'ACTIVE'
        elif cmd == 'STOPBIT':
            self.state = 'INACTIVE'
        elif cmd == 'DATA':
            # Send just the value of the received data packet without the individual bits
            self.send_data_value(data_value_and_bits[0], rxtx)