Belajar Itu Mengasikkan

• 2 x 8 modul LCD, menggunakan Hitachi HD44780 compatible controller
• Kontras kontrol pot
• 4 tombol untuk input pengguna
• Dapat digunakan dengan LCD kedua pada papan demo Parallax BS2p 

' -----[ I/O Definitions ]-------------------------------------------------
E PIN 1 ' LCD Enable (1 = enabled)
RW PIN 2 ' Read/Write\
RS PIN 3 ' Reg Select (1 = char)
LcdDirs VAR DIRB ' dirs for I/O redirection
LcdBusOut VAR OUTB
LcdBusIn VAR INB

' -----[ Constants ]-------------------------------------------------------

#DEFINE _LcdReady = ($STAMP = BS2P) OR ($STAMP = BS2PE)
LcdCls CON $01 ' clear the LCD
LcdHome CON $02 ' move cursor home
LcdCrsrL CON $10 ' move cursor left
LcdCrsrR CON $14 ' move cursor right
LcdDispL CON $18 ' shift chars left
LcdDispR CON $1C ' shift chars right
LcdDDRam CON $80 ' Display Data RAM control
LcdCGRam CON $40 ' Character Generator RAM
LcdLine1 CON $80 ' DDRAM address of line 1
LcdLine2 CON $C0 ' DDRAM address of line 2
LcdScrollTm CON 250 ' LCD scroll timing (ms)

' -----[ Variables ]-------------------------------------------------------
addr VAR Word ' address pointer
crsrPos VAR Byte ' cursor position
char VAR Byte ' character sent to LCD
idx VAR Byte ' loop counter
scan VAR Byte ' loop counter
buttons VAR Nib
btnA VAR buttons.BIT0 ' left-most button
btnB VAR buttons.BIT1
btnC VAR buttons.BIT2
btnD VAR buttons.BIT3 ' right-most
btnDemo VAR Byte ' loop counter

' -----[ EEPROM Data ]-----------------------------------------------------
CC0 DATA $0E, $1F, $1C, $18, $1C, $1F, $0E, $00 ' char 0
CC1 DATA $0E, $1F, $1F, $18, $1F, $1F, $0E, $00 ' char 1
CC2 DATA $0E, $1F, $1F, $1F, $1F, $1F, $0E, $00 ' char 2
Smiley DATA $00, $0A, $0A, $00, $11, $0E, $06, $00 ' smiley
Msg1 DATA "PARALLAX", 0
Msg2 DATA " BASIC STAMP ", 3, " ", 0
Msg3 DATA "Type =", 0
Msg4 DATA "Buttons:", 0
StampId0 DATA " BS2", 0
StampId1 DATA " BS2e", 0
StampId2 DATA "BS2sx", 0
StampId3 DATA " BS2p", 0
StampId4 DATA "BS2pe", 0

' -----[ Initialization ]--------------------------------------------------

Initialize:
NAP 5 ' let LCD self-initialize
DIRL = %11111110 ' setup pins for LCD
LCD_Init:
#IF _LcdReady #THEN
LCDCMD E, 110000 : PAUSE 5 ' 8-bit mode
LCDCMD E, 110000 : PAUSE 0
LCDCMD E, 110000 : PAUSE 0

LCDCMD E, 100000 : PAUSE 0 ' 4-bit mode
LCDCMD E, 101000 : PAUSE 0 ' 2-line mode
LCDCMD E, 001100 : PAUSE 0 ' no crsr, no blink
LCDCMD E, 000110 ' inc crsr, no disp shift
#ELSE
LcdBusOut = 11 ' 8-bit mode
PULSOUT E, 3 : PAUSE 5
PULSOUT E, 3 : PAUSE 0
PULSOUT E, 3 : PAUSE 0
LcdBusOut = 10 ' 4-bit mode
PULSOUT E, 3
char = 101000 ' 2-line mode
GOSUB LCD_Command
char = 001100 ' on, no crsr, no blink
GOSUB LCD_Command
char = 000110 ' inc crsr, no disp shift
GOSUB LCD_Command
#ENDIF
Download_Chars: ' download custom chars
char = LcdCGRam ' point to CG RAM
GOSUB LCD_Command ' prepare to write CG data
FOR idx = CC0 TO (Smiley + 7) ' build 4 custom chars
READ idx, char ' get byte from EEPROM
GOSUB LCD_Write_Char ' put into LCD CG RAM
NEXT

' -----[ Program Code ]----------------------------------------------------
Main:
char = LcdCls ' clear the LCD
GOSUB LCD_Command
PAUSE 500
Write_Parallax:
addr = Msg1 ' point to message
GOSUB LCD_Put_String ' write it
Scroll_Message:
crsrPos = LcdLine2 ' scroll on line 2
addr = Msg2 ' point to msg
GOSUB LCD_Scroll_String ' scroll it
Pac_Man: ' Pac-Man animation
FOR idx = 0 TO 7 ' cover 8 characters
FOR scan = 0 TO 4 ' 5 characters in animation
char = LcdLine1 + idx ' position cursor
GOSUB LCD_Command

LOOKUP scan, [0, 1, 2, 1, " "], char ' select "frame"
GOSUB LCD_Write_Char ' write animation character
PAUSE 75 ' delay between chars
NEXT
NEXT
Show_Stamp_Type:
char = LcdCls ' clear the LCD
GOSUB LCD_Command
PAUSE 100
addr = Msg3 ' display "Type ="
GOSUB LCD_Put_String
char = LcdLine2 + 3 ' move cursor to 2nd line
GOSUB LCD_Command

#SELECT $STAMP ' check type at compile
#CASE BS2
addr = StampId0
#CASE BS2E
addr = StampId1
#CASE BS2SX
addr = StampId2
#CASE BS2P
addr = StampId3
#CASE BS2PE
addr = StampId4
#ENDSELECT
GOSUB LCD_Put_String ' display type on LCD
PAUSE 2000
Show_Buttons:
char = LcdCls ' clear the LCD
GOSUB LCD_Command
PAUSE 100
addr = Msg4 ' write "Buttons:"
GOSUB LCD_Put_String

FOR btnDemo = 1 TO 100
GOSUB LCD_Get_Buttons ' read/debounce buttons
char = LcdLine2 + 2 ' show on 2nd line
GOSUB LCD_Command
FOR idx = 0 TO 3 ' display buttons
IF buttons.LOWBIT(idx) THEN
char = "A" + idx ' button letter if pressed
ELSE
char = "-" ' otherwise dash
ENDIF
GOSUB LCD_Write_Char
NEXT

NEXT
GOTO Main ' run demo again
END

' -----[ Subroutines ]-----------------------------------------------------
' Writes stored (in DATA statement) zero-terminated string to LCD
' -- position LCD cursor
' -- point to 0-terminated string (first location in 'addr')
LCD_Put_String:
DO
READ addr, char
IF (char = 0) THEN EXIT
GOSUB LCD_Write_Char
addr = addr + 1
LOOP
RETURN

' Scroll a message across LCD line
' -- set starting position in 'crsrPos'
' -- point to 0-terminated string (first location in 'addr')
' -- strings should be padded with eight spaces on each end
LCD_Scroll_String:
DO
char = crsrPos ' move to start of window
GOSUB LCD_Command
FOR idx = 0 TO 7 ' write chars in window
READ (addr + idx), char
IF (char = 0) THEN EXIT ' stop if end of string
GOSUB LCD_Write_Char
NEXT
IF (char = 0) THEN EXIT
addr = addr + 1 ' scroll
PAUSE LcdScrollTm
LOOP
RETURN

' Send command to LCD
' -- put command byte in 'char'
LCD_Command: ' write command to LCD
#IF _LcdReady #THEN
LCDCMD E, char

RETURN
#ELSE
LOW RS
GOTO LCD_Write_Char
#ENDIF

' Write character to current cursor position
' -- but byte to write in 'char'
LCD_Write_Char: ' write character to LCD
#IF _LcdReady #THEN
LCDOUT E, 0, [char]
#ELSE
LcdBusOut = char.HIGHNIB ' output high nibble
PULSOUT E, 3 ' strobe the Enable line
LcdBusOut = char.LOWNIB ' output low nibble
PULSOUT E, 3
HIGH RS ' return to character mode
#ENDIF
RETURN

' Reads byte from LCD
' -- put byte address in 'addr'
' -- returns byte read in 'char'
LCD_Read_Char: ' read character from LCD
#IF _LcdReady #THEN
LCDIN E, addr, [char]
#ELSE
char = addr ' move cursor
GOSUB LCD_Command
HIGH RS ' data command
HIGH RW ' read
LcdDirs = 00 ' make LCD bus inputs
HIGH E
char.HIGHNIB = LcdBusIn ' get high nibble
LOW E
HIGH E
char.LOWNIB = LcdBusIn ' get low nibble
LOW E
LcdDirs = %1111 ' return data lines to
outputs
LOW RW
#ENDIF
RETURN

' Read and debounce the LCD AppMod buttons
LCD_Get_Buttons:
LcdDirs = 00 ' make LCD bus inputs
buttons = %1111 ' assume all pressed
FOR scan = 1 TO 10
buttons = buttons & LcdBusIn ' make sure button held
PAUSE 5 ' debounce 10 x 5 ms
NEXT
LcdDirs = %1111 ' return bus to outputs
RETURN

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