NAME
    Device::CurrentCost - Perl modules for Current Cost energy monitors

VERSION
    version 1.142240

SYNOPSIS
      use Device::CurrentCost;
      my $envy = Device::CurrentCost->new(device => '/dev/ttyUSB0');

      $|=1; # don't buffer output

      while (1) {
        my $msg = $envy->read() or next;
        print $msg->summary, "\n";
      }

      use Device::CurrentCost::Constants;
      my $classic = Device::CurrentCost->new(device => '/dev/ttyUSB1',
                                             type => CURRENT_COST_CLASSIC);
      # ...

      open my $cclog, '<', 'currentcost.log' or die $!;
      my $cc = Device::CurrentCost->new(filehandle => $cclog);

      while (1) {
        my $msg = $cc->read() or next;
        print $msg->summary, "\n";
      }

DESCRIPTION
    Module for reading from Current Cost energy meters.

    IMPORTANT: This is an early release and the API is still subject to
    change.

    The API for history is definitely not complete. This will change soon
    and an mechanism for aggregating the history (which is split across many
    messages) should be added.

METHODS
  "new(%parameters)"
    This constructor returns a new Current Cost device object. The supported
    parameters are:

    device
        The name of the device to connect to. The value should be a tty
        device name, e.g. "/dev/ttyUSB0" but a pipe or plain file should
        also work. This parameter is mandatory if filehandle is not given.

    filehandle
        A filehandle to read from. This parameter is mandatory if device is
        not given.

    type
        The type of the device. Currently either "CURRENT_COST_CLASSIC" or
        "CURRENT_COST_ENVY". The default is "CURRENT_COST_ENVY".

    baud
        The baud rate for the device. The default is derived from the type
        and is either 57600 (for Envy) or 9600 (for classic).

    history_callback
        A function, taking a sensor id, a time interval and a hash reference
        of data as arguments, to be called every time a new complete set of
        history data becomes available. The data hash reference has keys of
        the number of intervals ago and values of the reading at that time.

  "device()"
    Returns the path to the device.

  "type()"
    Returns the type of the device.

  "baud()"
    Returns the baud rate.

  "filehandle()"
    Returns the filehandle being used to read from the device.

  "serial_port()"
    Returns the Device::SerialPort object for the device.

  "open()"
    This method opens the serial port and configures it.

  "read($timeout)"
    This method blocks until a new message has been received by the device.
    When a message is received a data structure is returned that represents
    the data received.

    IMPORTANT: This API is still subject to change.

  "read_one(\$buffer)"
    This method attempts to remove a single Current Cost message from the
    buffer passed in via the scalar reference. When a message is removed a
    data structure is returned that represents the data received. If
    insufficient data is available then undef is returned.

    IMPORTANT: This API is still subject to change.

  "sensor_history($sensor, $interval)"
    This method returns the most recent complete sensor data for the given
    sensor and the given interval (where interval must be one of 'hours',
    'days', 'months' or 'years'). The return value is a hash reference with
    keys for 'time' and 'data'. The 'time' value is the time (in seconds
    since epoch). The 'data' value is a hash reference with keys of the
    number of intervals ago and values of the reading at that time.

    It returns undef if no history data has been received yet.

AUTHOR
    Mark Hindess <soft-cpan@temporalanomaly.com>

COPYRIGHT AND LICENSE
    This software is copyright (c) 2014 by Mark Hindess.

    This is free software; you can redistribute it and/or modify it under
    the same terms as the Perl 5 programming language system itself.

