boswatch.decoder.pocsagDecoder.PocsagDecoder Class Reference

POCSAG decoder class. More...

Static Public Member Functions
def	decode (data)
	Decodes POCSAG.

Static Protected Member Functions
def	_getBitrateRicSubric (data)
	Gets the Bitrate, Ric and Subric from data.

Detailed Description

POCSAG decoder class.

This class decodes POCSAG data.
First step is to validate the data and _check if the format is correct.
In the last step a valid BOSWatch packet is created and returned

Member Function Documentation

decode()

def boswatch.decoder.pocsagDecoder.PocsagDecoder.decode (   data )

static

Decodes POCSAG.

    @param data: POCSAG for decoding
    @return BOSWatch POCSAG packet or None

    def decode(data):
        r"""!Decodes POCSAG
 
        @param data: POCSAG for decoding
        @return BOSWatch POCSAG packet or None"""
        bitrate, ric, subric = PocsagDecoder._getBitrateRicSubric(data)
 
        if re.search("[0-9]{7}", ric) and re.search("[1-4]", subric):
            if "Alpha:" in data:
                message = data.split('Alpha:   ')[1].strip()
                message = message.replace('<NUL>', '').replace('<NUL', '').replace('< NUL>', '').replace('<EOT>', '').strip()
            else:
                message = ""
            subricText = subric.replace("1", "a").replace("2", "b").replace("3", "c").replace("4", "d")
 
            logging.debug("found valid POCSAG")
 
            bwPacket = Packet()
            bwPacket.set("mode", "pocsag")
            bwPacket.set("bitrate", bitrate)
            bwPacket.set("ric", ric)
            bwPacket.set("subric", subric)
            bwPacket.set("subricText", subricText)
            bwPacket.set("message", message)
 
            return bwPacket
 
        logging.warning("no valid POCSAG")
        return None
 

_getBitrateRicSubric()

def boswatch.decoder.pocsagDecoder.PocsagDecoder._getBitrateRicSubric (   data )

staticprotected

Gets the Bitrate, Ric and Subric from data.

    @param data: POCSAG data string
    @return bitrate
    @return ric
    @return subric

    def _getBitrateRicSubric(data):
        r"""!Gets the Bitrate, Ric and Subric from data
 
        @param data: POCSAG data string
        @return bitrate
        @return ric
        @return subric"""
        bitrate, ric, subric = "0", "0", "0"
 
        if "POCSAG512:" in data:
            bitrate = "512"
            ric = data[20:27].replace(" ", "").zfill(7)
            subric = str(int(data[39]) + 1)
 
        elif "POCSAG1200:" in data:
            bitrate = "1200"
            ric = data[21:28].replace(" ", "").zfill(7)
            subric = str(int(data[40]) + 1)
 
        elif "POCSAG2400:" in data:
            bitrate = "2400"
            ric = data[21:28].replace(" ", "").zfill(7)
            subric = str(int(data[40]) + 1)
 
        return bitrate, ric, subric