Flags.cs

// Licensed to the .NET Foundation under one or more agreements.
// The .NET Foundation licenses this file to you under the MIT license.

using System;

namespace Iot.Device.CharacterLcd
{
    // Command flags are found on page 24/25 of the HD4478U spec.
    [Flags]
    internal enum DisplayEntryMode : byte
    {
        /// <summary>
        /// Enabled to shift the display left when <see cref="Increment"/> is enabled
        /// or right if <see cref="Increment"/> is disabled.
        /// </summary>
        /// <remarks>The "S" option from the datasheet.</remarks>
        DisplayShift = 0b_0001,

        /// <summary>
        /// Set to increment the CGRAM/DDRAM address by 1 when a character code is
        /// written into or read from and moves the cursor to the right. Disabling
        /// decrements and moves the cursor to the left.
        /// </summary>
        /// <remarks>The "I/D" option from the datasheet.</remarks>
        Increment = 0b_0010,

        /// <summary>
        /// The flag for entry mode- must be set.
        /// </summary>
        Command = 0b_0100,
    }

    [Flags]
    internal enum DisplayControl : byte
    {
        /// <summary>
        /// Set for enabling cursor blinking.
        /// </summary>
        /// <remarks>The "B" option from the datasheet.</remarks>
        BlinkOn = 0b_0001,

        /// <summary>
        /// Set for enabling the cursor.
        /// </summary>
        /// <remarks>The "C" option from the datasheet.</remarks>
        CursorOn = 0b_0010,

        /// <summary>
        /// Set for enabling the entire display.
        /// </summary>
        /// <remarks>The "D" option from the datasheet.</remarks>
        DisplayOn = 0b_0100,

        /// <summary>
        /// The flag for display control- must be set.
        /// </summary>
        Command = 0b_1000
    }

    [Flags]
    internal enum DisplayShift : byte
    {
        /// <summary>
        /// When set shifts right, otherwise shifts left.
        /// </summary>
        /// <remarks>The "R/L" option from the datasheet.</remarks>
        Right = 0b_0000_0100,

        /// <summary>
        /// When set shifts the display when data is entered, otherwise shifts the cursor.
        /// </summary>
        /// <remarks>The "S/C" option from the datasheet.</remarks>
        Display = 0b_0000_1000,

        /// <summary>
        /// The flag for display and cursor shift- must be set.
        /// </summary>
        Command = 0b_0001_0000
    }

    [Flags]
    internal enum DisplayFunction : byte
    {
        /// <summary>
        /// When set, commands (other than <see cref="DisplayFunction"/>) are from the
        /// extended (NXP/Philips, Sitronix) instruction set. For Sitronix (ST7036) this
        /// is extended intstruction set 1.
        /// </summary>
        /// <remarks>
        /// The "H" option from the NXP datasheet. The "IS1" option from Sitronix.
        /// Not all driver ICs support this.
        /// </remarks>
        ExtendedInstructionSet = 0b_0000_0001,

        /// <summary>
        /// If set font is 5x10, otherwise font is 5x8.
        /// </summary>
        /// <remarks>
        /// The "F" option from the HD44780 datasheet.
        ///
        /// The displays that supported 5x10 are extremely rare.
        ///
        /// On NXP/Philips chips this is the "M" option that
        /// controls the number of display lines. When set the
        /// driver is set to 2 line x 16 characters. Otherwise
        /// the driver is set to 1 line by 32 characters.
        ///
        /// For Sitronix, this is referred to as "DH" and sets
        /// double height mode.
        /// </remarks>
        Font5x10 = 0b_0000_0100,

        /// <summary>
        /// If set display is two line, otherwise display is one line.
        /// </summary>
        /// <remarks>
        /// The "N" option from the datasheet.
        ///
        /// When set to one line, shifting the display right pulls
        /// address 0x4F to the 1st display position. When set to two
        /// lines, shifting right pulls 0x27 for the first line and
        /// 0x67 for the second.
        /// </remarks>
        TwoLine = 0b_0000_1000,

        /// <summary>
        /// If set display uses all eight data pins, otherwise display uses
        /// four data pins.
        /// </summary>
        /// <remarks>The "DL" option from the datasheet.</remarks>
        EightBit = 0b_0001_0000,

        /// <summary>
        /// The flag for setting display function- must be set.
        /// </summary>
        Command = 0b_0010_0000
    }
}