# to 0? No it is not. DMX receivers don't add implicit

            # zeros there.

            buf = bytes([0]) + buf[:self.lastDmxChannel]

            if logAllDmx.isEnabledFor(logging.DEBUG):

                # for testing fps, smooth fades, etc

                logAllDmx.debug(

                    '%s: %s...' %

                    (self.shortId(), ' '.join(map(str, buf[:32]))))

            self.dmx.send_dmx(buf)

class Udmx(BackgroundLoopOutput):

    _reconnections = scales.IntStat('reconnections')

    _connected = scales.IntStat('connected')

    def __init__(self, uri, bus, address, lastDmxChannel, rate=22):

        self.bus = bus

        self.address = address

        self.lastDmxChannel = lastDmxChannel

        self.dev = None

        super().__init__(uri, rate=rate)

                                          scales.IntStat('overflow'),

                                          scales.IntStat('ioError'),

                                          scales.IntStat('pipeError')

        )

        self.reconnect()

    def reconnect(self):

        self._connected = 0

        from pyudmx import pyudmx

        self.dev = pyudmx.uDMXDevice()

        if not self.dev.open(bus=self.bus, address=self.address):

            raise ValueError("dmx open failed")

        log.info(f'opened {self.dev}')

        self._connected = 1

        self._reconnections += 1

    #def update(self, buf:bytes):

    #    self._write(buf)

    #def _loop(self):

    #    pass

    def _write(self, buf):

        if not self.dev:

            log.info('%s: trying to connect', self.shortId())

            raise ValueError()

        self._writeStats.fps.mark()

        with self._writeStats.call.time():

            try:

                if not buf:

                    logAllDmx.debug('%s: empty buf- no output',