#!/usr/bin/env ruby
# $Paefchen: ruby/snd/snd.rb,v 1.1 2008/04/04 12:17:55 as Exp $

module SND

	class MB
		def initialize addr, port=502, slaveaddr=0
			@addr = addr
			@port = port
			@slaveaddr = slaveaddr
		end

		#def read_input; end
		#def read_inputs; end
		#def read_coil; end
		#def read_coils; end
		#def write_coil; end
		#def write_coils; end
		#def read_input_register; end
		#def read_input_registers; end
		#def read_input_registers; end
		#def write_registers; end

		def read_holding_register register
			raw("read_holding_register #{register}").split('=')[1].to_i
		end
		
		def write_register register, value
			raw("write_register #{register} #{value.to_i}")
		end
		
	private
		def raw	text
			`../mb_tcpclient #{@addr} #{@port} #{@slaveaddr} #{text}`
		end
	end

	class Setting
		def initialize addr, port=502, slaveaddr=0
			@mb = MB.new addr, port, slaveaddr
			
			@volumen_min = 100
			@volumen_max = 250
		end

		def volumen_fadeto to
			now = volumen_get
			
			return true if now == to
			
			return volumen_set(0) if to == 0
				
			to = @volumen_min if to < @volumen_min
			to = @volumen_max if to > @volumen_max			
			
			if now < to
				(now+1).upto(to) { |i| volumen_set i }
			else
				(now-1).downto(to) { |i| volumen_set i }
			end
		end
				
		def volumen_get
			@mb.read_holding_register 0	
		end
		
		def volumen_set value
			@mb.write_register 0, value
		end
	end
end