Help with LCD Scroll

[Art]

The way I read it, that should be what the version Tabsoft posted does.
I might be seeing something else in my mind, or does it just scroll the wrong direction?

Basically, this could be written simpler if it never had to be a real program.
You could ditch the line buffer and rotate routine, step the index where you read the lookup table,
check it’s bounds, and write 20 char to LCD at a time directly to LCD.

Usually you want to look at, or change the display data, so I’d normally prepare
all lines of text in buffers, and write all four lines from the line's start positions for every frame.
even if the text doesn’t change or move.
If you never write past the end of a line the text can’t wrap.

[Tabsoft]

Carrying on with what Art mentioned previously.
I looked pretty closely at the LCD controller and can not find away to disable the line wrapping when you use a shift command.
Looks like that is the way the controller works.

That being said I put together this program that will shift the message from Right to Left.
See if this helps.

'****************************************************************
'*  Name    : LCDScroll_v1.pbp                                                                      *
'*  Author  : TABSoft                                                                                    *
'*  Notice  : Copyright (c) 2015 TABSoft                                                         *
'*          : All Rights Reserved                               *
'*  Date    : 2/6/2015                                          *
'*  Version : 1.0                                               *
'*  Notes   :                                                   *
'*          :                                                   *
'****************************************************************

'*****PIC MCU Configuration Fuses (MPASM)*****
#IF __PROCESSOR__ = "18F4620"
    #CONFIG
        CONFIG OSC = ECIO6            ; EC oscillator, port function on RA6
        ;CONFIG OSC = INTIO67	      ; Internal oscillator block, port function on RA6 and RA7
        ;CONFIG  WDT = OFF             ; WDT disabled (control is placed on the SWDTEN bit)
        CONFIG  FCMEN = OFF           ; Fail-Safe Clock Monitor disabled
        CONFIG  IESO = OFF            ; Oscillator Switchover mode disabled
        CONFIG  PWRT = OFF            ; PWRT disabled
        CONFIG  BOREN = SBORDIS       ; Brown-out Reset enabled in hardware only (SBOREN is disabled)
        CONFIG  BORV = 3              ; Minimum setting
        CONFIG  WDT = ON              ; WDT enabled
        CONFIG  WDTPS = 512           ; 1:512
        CONFIG  CCP2MX = PORTC        ; CCP2 input/output is multiplexed with RC1
        CONFIG  PBADEN = OFF          ; PORTB<4:0> pins are configured as digital I/O on Reset
        CONFIG  LPT1OSC = OFF         ; Timer1 configured for higher power operation
        CONFIG  MCLRE = ON            ; MCLR pin enabled; RE3 input pin disabled
        CONFIG  STVREN = ON           ; Stack full/underflow will cause Reset
        CONFIG  LVP = OFF             ; Single-Supply ICSP disabled
        CONFIG  XINST = OFF           ; Instruction set extension and Indexed Addressing mode disabled (Legacy mode)
        CONFIG  DEBUG = OFF           ; Background debugger disabled, RB6 and RB7 configured as general purpose I/O pins
        CONFIG  CP0 = OFF             ; Block 0 (000800-003FFFh) not code-protected
        CONFIG  CP1 = OFF             ; Block 1 (004000-007FFFh) not code-protected
        CONFIG  CP2 = OFF             ; Block 2 (008000-00BFFFh) not code-protected
        CONFIG  CP3 = OFF             ; Block 3 (00C000-00FFFFh) not code-protected
        CONFIG  CPB = OFF             ; Boot block (000000-0007FFh) not code-protected
        CONFIG  CPD = OFF             ; Data EEPROM not code-protected
        CONFIG  WRT0 = OFF            ; Block 0 (000800-003FFFh) not write-protected
        CONFIG  WRT1 = OFF            ; Block 1 (004000-007FFFh) not write-protected
        CONFIG  WRT2 = OFF            ; Block 2 (008000-00BFFFh) not write-protected
        CONFIG  WRT3 = OFF            ; Block 3 (00C000-00FFFFh) not write-protected
        CONFIG  WRTC = OFF            ; Configuration registers (300000-3000FFh) not write-protected
        CONFIG  WRTB = OFF            ; Boot Block (000000-0007FFh) not write-protected
        CONFIG  WRTD = OFF            ; Data EEPROM not write-protected
        CONFIG  EBTR0 = OFF           ; Block 0 (000800-003FFFh) not protected from table reads executed in other blocks
        CONFIG  EBTR1 = OFF           ; Block 1 (004000-007FFFh) not protected from table reads executed in other blocks
        CONFIG  EBTR2 = OFF           ; Block 2 (008000-00BFFFh) not protected from table reads executed in other blocks
        CONFIG  EBTR3 = OFF           ; Block 3 (00C000-00FFFFh) not protected from table reads executed in other blocks
        CONFIG  EBTRB = OFF           ; Boot Block (000000-0007FFh) not protected from table reads executed in other blocks

    #ENDCONFIG
#else
    #ERROR "This program requires a PIC 18F4620 MCU"
#endif

OSCCON = $60  ' Set PIC to 4Mhz & ECIO Clock Mode

 DEFINE OSC 4
   ADCON0.0 = 0  ' A/D Converter module is disabled   
   ADCON1 = $0F  ' %0000 1111 AN2=VSS, AN3=VDD, AN12-0 = Digital 
   ADCON2 = $00  ' %0000 0000
   TRISB = %11111111 ' Set PORTB as input
   INTCON2.7 = 0 ' Enable PORTB pullups
   TRISC = TRISC & %11011111   ' Set PORTC pin directions (pin5 output to RTC VCC2)


'*****Define LCD registers and bits*****
define LCD_BITS      4  '8  '4
define LCD_LINES     2  ' Set to number of lines for the LCD
Define LCD_DREG      PORTD
Define LCD_DBIT      4  '0  '4
Define LCD_RSREG     PORTE
Define LCD_RSBIT     0
Define LCD_EREG      PORTE
Define LCD_EBIT      1
define LCD_RWREG     PORTE
define LCD_RWBIT     2
define LCD_COMMANDUS 1500
define LCD_DATAUS    44

'
' Software Constants
'
LastLCDCol con 19
' number of Columns in your LCD

'
' Software variables
'
LCD_Line1 var byte [50] 'Array to hold the Line 1 LCD Message (0 to 49)
L1_ArrayLen var byte    'Length of LCD Line 1 Message Array
StartPos var byte       'Pointer to start of message in Array
idx var byte            'Current index into Message Array
MaxCount var byte       'Loop counter max number
LoopCount var byte      'Loop Counter
i var byte


'*****Intialize Variables*****
L1_ArrayLen=50

'*****Initialize LCD Line 1 Message Array*****
arraywrite LCD_Line1, ["This is a test of the scrolling text screen...... "]


'*****Initialize LCD*****
   Low LATE.2  		    ' LCD R/W line low (W)
   Pause 500       	  ' Wait .5 second for LCD to Initialize


'
' Program
'


mainloop:
    MaxCount = 81
    LoopCount = 0
    StartPos = 0
    
    do
        lcdout $FE, $80
        LoopCount = LoopCount + 1
        for i = 0 to LastLCDCol
            idx = StartPos + i
            if idx > (L1_ArrayLen - 1) then
                idx = (idx // L1_ArrayLen)
            endif
            lcdout LCD_Line1(idx)    
        next i
        StartPos = StartPos + 1
        if StartPos > (L1_ArrayLen - 1) then
            StartPos = 0
        endif
        pause 500    'Adjust for best scrolling appearance
    loop while LoopCount < MaxCount
    pause 250
    goto mainloop   'Do it forever

    end     'Got here by mistake

[ozarkshermit]

Thanks TABSoft

Sorry for the late response

Ken