bcr2000.rb

$LOAD_PATH.unshift(File.dirname(__FILE__))

require 'midi-winmm'
# tested with midi-winmm, but I assume will work with alsa-rawmidi

class Numeric
   def to_hex_str
     "%02x" % self
   end
end

class String
  def to_hex_str
     unpack('U' * length).collect { |x| "%02x" % x }.join
  end
end

module MIDIWinMM
  module Device
    attr :id, :info, :type, :name, :enabled
  end
end

# Every SysEx message sent to the BCR2000 or BCF2000
# uses a language called BCL or B-Control Language..
# Regrettably, Behringer never released the specs
# which makes it hard as hell to program.
#
# From here on, the BCR2000 and BCF2000  will simply
# be called "BCR" and "BCF", respectably. 
# When refering to both devices, I'll simply write "BC".
module BControl
  module Definitions
    SysExStart = 0xf0
    SysExEnd = 0xf7
    SysExBehringer = [0x00, 0x20, 0x32]

    Any = 0x7F
    BCF2000 = 0x14
    BCR2000 = 0x15
  end

  module SysEx
    include Definitions

    # Generates an array of bytes that results in a sysex message
    def self.generate(id, model, command, data)
      result = [] 
      result << SysExStart
      result = result + SysExBehringer
      result << id - 1 << model << command
      # TODO: if data.is_a?(Array) then ADD the data array, not CONCAT
      result << data 
      result << SysExEnd
    end
  end

  # Cached list of devices. Use DeviceList#refresh! to ..well.. refresh the list.
  class DeviceList < Array
    def initialize; refresh!; end
    def refresh!; replace(MIDIWinMM::Device.all); end
    def all_of_type(type); find_all { |d| d.type == type }; end
  end
  Devices = DeviceList.new

  class Device
    attr :id, :model, :opened

    def initialize(&blk)
      @input_device = nil
      @output_device = nil
      @opened = false

      @id = Definitions::Any
      @model = Definitions::Any
    end

    def input_device(&blk)
      raise("Cannot change input device when opened") if @open
      block_given? ? @input_device = Devices.all_of_type(:input).find(&blk) : @input_device
    end

    def output_device(&blk)
      raise("Cannot change output device when opened") if @open
      block_given? ? @output_device = Devices.all_of_type(:output).find(&blk) : @output_device
    end

    def input_device?; !!@input_device; end
    def output_device?; !!@output_device; end

    def open?; @opened; end
    alias :opened? :open

    def id=(val)
      @id = (1..16).include?(val) ? val : Definitions::Any
    end

    def model=(val)
      is_valid_model = [Definitions::BCR2000, Definitions::BCF2000].include?(val)
      @model = is_valid_model ? val : Definitions::Any
    end

    def open
      @opened = true
      @input_device.open if input_device?
      @output_device.open if output_device?
    end

    def close
      @opened = false
      @input_device.close if input_device?
      @output_device.close if output_device?
    end

    private # protected

    def generate_sysex(command, data)
      SysEx.generate(@id, @model, command, data)
    end
  end

  class BCR2000 < Device
    def initialize(id = Definitions::Any)
      @id = id
      @model = Definitions::BCR2000
    end

    def select_preset(preset_number)
      sysex_message = generate_sysex(0x22, preset_number - 1)
      if output_device? && open?
        @output_device.puts(sysex_message)
      else
        sysex_message
      end
    end
  end
end

# ======================================================

require 'pp'


bcr2000 = BControl::BCR2000.new
bcr2000.id = 1
bcr2000.output_device { |d| d.name == "BCR2000" } # { |d| d.id == 0 }

bcr2000.open
bcr2000.select_preset(5)
bcr2000.close