note
	description: "[
		Hitachi HD44780 controller display size configurations.
	]"
	legal   : "See notice at end of class."
	status  : "See notice at end of class.";
	author  : "Paul Bates (paul.a.bates@gmail.com)"
	date    : "$Date$"
	revision: "$Revision$"

expanded class
	HD44780_DISPLAY_CONFIG

inherit
	ENUM_TYPE [NATURAL_16]

create
	default_create,
	make

convert
	make ({NATURAL_16}),
	item: {NATURAL_16}

feature -- Access

	lines: NATURAL_8
			-- Number of line in the current configuration
		do
			Result := (line_bitmask & item).to_natural_8
		end

	columns: NATURAL_8
			-- Number of line in the current configuration
		do
			Result := (columns_bitmask & item).bit_shift_right (8).to_natural_8
		end

feature {NONE} -- Access

	line_bitmask: NATURAL_16 = 0b0000000000000111
			-- Bit mask for extracting the line value.

	columns_bitmask: NATURAL_16 = 0b0011111100000000
			-- Bit mask for extracting the column value.

feature -- Members

	display_16x2: NATURAL_16 = 0b0001000000000010
			-- Configuration for a 16 character x 2 rows display

	display_16x4: NATURAL_16 = 0b0001000000000100
			-- Configuration for a 16 character x 4 rows display

	display_20x2:  NATURAL_16 = 0b0001010000000010
			-- Configuration for a 20 character x 2 rows display

	display_20x4:  NATURAL_16 = 0b0001010000000100
			-- Configuration for a 20 character x 4 rows display

	display_40x2:  NATURAL_16 = 0b0010100000000010
			-- Configuration for a 40 character x 2 rows display

feature {NONE} -- Members

	members: ARRAY [NATURAL_16]
			-- <Precursor>
		once
			Result := <<
				display_16x2,
				display_16x4,
				display_20x2,
				display_20x4,
				display_40x2 >>
		end

end