Unit HD44780
From Ultibo.org
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Description
Hitachi HD44780 LCD Controller Driver unit
The Hitachi HD44780 is a dot matrix liquid crystal display controller. It supports 5x8 or 5x10 characters and includes a 240 character font in ROM, 80 bytes of character RAM and 64 bytes of character generator RAM for custom characters.
The device support 4 bit or 8 bit modes, and has a range of standard functions for display clear, display on/off, cursor on/off, character blink, cursor shift etc.
This unit creates a Console device to represent the LCD and provides the standard console device functions (where appropriate) to draw text, clear the screen, scroll text and manage the cursor.
Currently only 4 bit mode is supported but extension to include 8 bit mode is possible with some additional setup and support functions.
Constants
HD44780 specific constants
HD44780_CONSOLE_* HD44780_CONSOLE_DESCRIPTION = 'Hitachi HD44780 LCD Controller';
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Description of HD44780 device |
HD44780 instruction
HD44780_* HD44780_CLEARDISPLAY = $01;
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HD44780_RETURNHOME = $02;
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HD44780_ENTRYMODESET = $04;
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HD44780_DISPLAYCONTROL = $08;
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HD44780_CURSORSHIFT = $10;
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HD44780_FUNCTIONSET = $20;
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HD44780_SETCGRAMADDR = $40;
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HD44780_SETDDRAMADDR = $80;
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HD44780 entry mode set
HD44780_ENTRYMODESET_* HD44780_ENTRYMODESET_RIGHT = $00;
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HD44780_ENTRYMODESET_LEFT = $02;
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HD44780_ENTRYMODESET_SHIFTINC = $01;
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HD44780_ENTRYMODESET_SHIFTDEC = $00;
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HD44780 display control
HD44780_DISPLAYCONTROL_* HD44780_DISPLAYCONTROL_DISPLAYON = $04;
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HD44780_DISPLAYCONTROL_DISPLAYOFF = $00;
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HD44780_DISPLAYCONTROL_CURSORON = $02;
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HD44780_DISPLAYCONTROL_CURSOROFF = $00;
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HD44780_DISPLAYCONTROL_BLINKON = $01;
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HD44780_DISPLAYCONTROL_BLINKOFF = $00;
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HD44780 cursor shift
HD44780_CURSORSHIFT_* HD44780_CURSORSHIFT_DISPLAY = $08;
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HD44780_CURSORSHIFT_CURSOR = $00;
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HD44780_CURSORSHIFT_RIGHT = $04;
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HD44780_CURSORSHIFT_LEFT = $00;
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HD44780 function set
HD44780_FUNCTIONSET_* HD44780_FUNCTIONSET_8BITMODE = $10;
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HD44780_FUNCTIONSET_4BITMODE = $00;
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HD44780_FUNCTIONSET_2LINE = $08;
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HD44780_FUNCTIONSET_1LINE = $00;
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HD44780_FUNCTIONSET_5X10DOTS = $04;
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HD44780_FUNCTIONSET_5X8DOTS = $00;
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HD44780 row offset
HD44780_ROW_OFFSETS* | 4 rows | |
HD44780_ROW_OFFSETS:array[0..3] of Byte = ($00,$40,$14,$54);
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Type definitions
HD44780 character
PHD44780Character = ^THD44780Character;
THD44780Character = array[0..7] of Byte;
HD44780 console
PHD44780Console = ^THD44780Console;
THD44780Console = record
| Console Properties | |
Console:TConsoleDevice;
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| HD44780 Properties | |
GPIO:PGPIODevice;
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The GPIO device this Console is connected to |
RS:LongWord;
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The GPIO pin for the RS line |
RW:LongWord;
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The GPIO pin for the RW line |
EN:LongWord;
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The GPIO pin for the EN line |
D4:LongWord;
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The GPIO pin for the D4 line |
D5:LongWord;
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The GPIO pin for the D5 line |
D6:LongWord;
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The GPIO pin for the D6 line |
D7:LongWord;
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The GPIO pin for the D7 line |
EntryMode:Byte;
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Current value of the Entry Mode settings |
FunctionSet:Byte;
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Current value of the Function Set settings |
DisplayControl:Byte;
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Current value of the Display Control settings |
| Cursor Properties | |
CursorX:Byte;
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CursorY:Byte;
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| Buffer Properties | |
Size:LongWord;
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Buffer:PByte;
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Public variables
None defined
Function declarations
HD44780 functions
function HD44780ConsoleCreate(GPIO:PGPIODevice; const Name:String; Width,Height,RS,RW,EN,D4,D5,D6,D7:LongWord):PConsoleDevice;
Description: To be documented
| Note | None documented |
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function HD44780ConsoleDestroy(Console:PConsoleDevice):LongWord;
Description: To be documented
| Note | None documented |
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HD44780 console functions
function HD44780ConsoleOpen(Console:PConsoleDevice):LongWord;
Description: Implementation of ConsoleDeviceOpen API for HD44780
| Note | Not intended to be called directly by applications, use ConsoleDeviceOpen instead. |
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function HD44780ConsoleClose(Console:PConsoleDevice):LongWord;
Description: Implementation of ConsoleDeviceClose API for HD44780
| Note | Not intended to be called directly by applications, use ConsoleDeviceClose instead. |
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function HD44780ConsoleClear(Console:PConsoleDevice; Color:LongWord):LongWord;
Description: Implementation of ConsoleDeviceClear API for HD44780
| Note | Not intended to be called directly by applications, use ConsoleDeviceClear instead. |
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function HD44780ConsoleScroll(Console:PConsoleDevice; X1,Y1,X2,Y2,Count,Direction:LongWord):LongWord;
Description: Implementation of ConsoleDeviceScroll API for HD44780
| Note | Not intended to be called directly by applications, use ConsoleDeviceScroll instead. |
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function HD44780ConsoleDrawChar(Console:PConsoleDevice; Handle:TFontHandle; Ch:Char; X,Y,Forecolor,Backcolor:LongWord):LongWord;
Description: Implementation of ConsoleDeviceDrawChar API for HD44780
| Note | Not intended to be called directly by applications, use ConsoleDeviceDrawChar instead. |
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function HD44780ConsoleDrawText(Console:PConsoleDevice; Handle:TFontHandle; const Text:String; X,Y,Forecolor,Backcolor,Len:LongWord):LongWord;
Description: Implementation of ConsoleDeviceDrawText API for HD44780
| Note | Not intended to be called directly by applications, use ConsoleDeviceDrawText instead. |
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function HD44780ConsoleDrawBlock(Console:PConsoleDevice; X1,Y1,X2,Y2,Color:LongWord):LongWord;
Description: Implementation of ConsoleDeviceDrawBlock API for HD44780
| Note | Not intended to be called directly by applications, use ConsoleDeviceDrawBlock instead. |
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function HD44780ConsoleDrawWindow(Console:PConsoleDevice; Handle:TWindowHandle; Flags:LongWord):LongWord;
Description: Implementation of ConsoleDeviceDrawWindow API for HD44780
| Note | Caller must hold the Window lock
Not intended to be called directly by applications, use ConsoleDeviceDrawWindow instead. |
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function HD44780ConsolePutText(Console:PConsoleDevice; Handle:TFontHandle; const Source,Dest:TConsolePoint; Buffer:PConsoleChar; Width,Height,Skip:LongWord):LongWord;
Description: Implementation of ConsoleDevicePutText API for HD44780
| Note | Not intended to be called directly by applications, use ConsoleDevicePutText instead. |
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function HD44780ConsoleGetPosition(Console:PConsoleDevice; Position:LongWord; var X1,Y1,X2,Y2:LongWord):LongWord;
Description: Implementation of ConsoleDeviceGetPosition API for HD44780
| Note | Not intended to be called directly by applications, use ConsoleDeviceGetPosition instead. |
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HD44780 helper functions
function HD44780WriteChar(Console:PHD44780Console; Ch:Char):LongWord;
Description: Write character data to the HD44780 device
| Note | Caller must hold the Console lock |
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function HD44780WriteData(Console:PHD44780Console; Value:Byte):LongWord;
Description: Write command data to the HD44780 device
| Note | Caller must hold the Console lock |
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function HD44780PulseEnable(Console:PHD44780Console):LongWord;
Description: Pulse the clock enable line off, on, off to send a command
| Note | Caller must hold the Console lock |
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function HD44780CursorHome(Console:PHD44780Console):LongWord;
Description: Return the cursor to the top left corner
| Note | Caller must hold the Console lock |
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function HD44780CursorBlink(Console:PHD44780Console; Blink:Boolean):LongWord;
Description: Set the cursor blinking to on or off
| Note | Caller must hold the Console lock |
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function HD44780CursorVisible(Console:PHD44780Console; Visible:Boolean):LongWord;
Description: Set the cursor to visible or not visible
| Note | Caller must hold the Console lock |
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function HD44780CursorPosition(Console:PHD44780Console; Row,Col:Byte):LongWord;
Description: Set the cursor position to Row, Col
| Note | Caller must hold the Console lock |
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function HD44780DisplayEnabled(Console:PHD44780Console; Enabled:Boolean):LongWord;
Description: Set the display state to on or off
| Note | Caller must hold the Console lock |
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function HD44780AddCharacter(Console:PHD44780Console; Location:Byte; Character:THD44780Character):LongWord;
Description: Add a custom character to the display
| Note | Caller must hold the Console lock |
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