Assembly Language across different microcontrollers question.

$MOD751
; **************************************************
;* *
; * HDM3224 Application Note V1.0 *
;* *
; **************************************************
; The processor clock speed is 16MHz.
; Cycle time is .750mS.
; Demo software to display a bonsai
; tree bitmap image and 4 lines of
; text on a 320 x 240 LCD.
org 00h
ljmp start ;program start
org 100h


; Initialize the 32241
; Text page 0000h 04afh
; Graphics page 04b0h 2a2fh
start:
    mov r1,#40h ;system set
    lcall comm32
    mov dptr,#msg1 ;ss param
    lcall data32
    mov r1,#44h ;scroll
    lcall comm32
    mov dptr,#msg2 ;scroll param
    lcall data32
    mov r1,#5dh ;csr form
    lcall comm32
    mov dptr,#msg3 ;csr param
    lcall data32
    mov r1,#4ch ;csrdir
    lcall comm32
    mov r1,#5ah ;hdot scr
    lcall comm32
    mov dptr,#msg18 ;hdot param
    lcall data32
    mov r1,#5bh ;overlay
    lcall comm32
    mov dptr,#msg4 ;ovrly param
    lcall data32
    mov r1,#59h ;disp on/off
    lcall comm32
    mov dptr,#msg5 ;disp param
    lcall data32

    ; clear the text page
    lcall clrtext

    ; display bitmap
    mov r1,#46h ;set cursor
    lcall comm32
    mov dptr,#msg6
    lcall data32
    mov r1,#42h ;mwrite
    lcall comm32
    mov dptr,#msg12
    lcall data32

    ; display text
    mov r1,#46h ;set cursor
    lcall comm32
    mov dptr,#msg7
    lcall data32
    mov r1,#42h ;mwrite
    lcall comm32
    mov dptr,#msg14
    lcall data32
    mov r1,#46h ;set cursor
    lcall comm32
    mov dptr,#msg8
    lcall data32
    mov r1,#42h ;mwrite
    lcall comm32
    mov dptr,#msg15
    lcall data32
    mov r1,#46h ;set cursor
    lcall comm32
    mov dptr,#msg9
    lcall data32
    mov r1,#42h ;mwrite
    lcall comm32
    mov dptr,#msg16
    lcall data32
    mov r1,#46h ;set cursor
    lcall comm32
    mov dptr,#msg10
    lcall data32
    mov r1,#42h ;mwrite
    lcall comm32
    mov dptr,#msg17
    lcall data32
    
sjmp $ ;stop



;*************************************************
;SUBROUTINES
; comm32 sends the byte in R1 to the
; 32241 display as a command
comm32:
    setb RA.2 ;a0=1=command

comm321:
    mov a,r1 ;get data byte
    mov RB,a
    clr RA.0 ;CS the display
    clr RA.1 ;strobe
    setb RA.1
    setb RA.0
    ret
    
; write32 sends the byte in R1 to the
; 32241 display as a data byte.
write32:
    clr RA.2 ;a0=0=data
    sjmp comm321
    
; data32 sends the message pointed to
; by the DPTR to the 32241 display.
data32:
    clr a ;get the byte
    movc a,@a+dptr
    cjne a,#0a1h,data321;done?
    ret

data321:
    mov r1,a
    lcall write32 ;send it
    inc dptr
    sjmp data32 ;next byte
    
; Clear text RAM on the 3224
clrtext:
    mov r1,#46h ;set cursor
    lcall comm32
    mov dptr,#msg13 ;cursor param
    lcall data32
    mov r1,#42h ;mwrite
    lcall comm32
    mov dptr,#msg11 ;all spaces
    lcall data32
    mov r1,#46h ;set cursor
    lcall comm32
    mov dptr,#msg6
    lcall data32
    ret


;************************************************
; TABLES AND DATA
; Initialization parameters for 3224.

msg1:
    db 30h,87h,07h,27h ;system set
    db 39h,0efh,28h,0h,0a1h

msg2:
    db 0,0,0efh,0b0h ;scroll
    db 04h,0efh,0,0
    db 0,0,0a1h

msg3:
    db 04h,86h,0a1h ;csr form

msg4:
    db 01h,0a1h ;overlay param

msg5:
    db 16h,0a1h ;disp on/off

msg6:
    db 0b0h,04h,0a1h ;set cursor to
    ;graphics page

msg7:
    db 31h,2h,0a1h ;set cursor
    ;text page
    ;1st line

msg8:
    db 59h,2,0a1h ;2nd line

msg9:
    db 81h,2,0a1h ;3rd line

msg10:
    db 0a9h,2,0a1h ;4th line
    ; 1200 spaces for text page clear
    ; The following table is not listed
    ; here, except for the first 8 bytes,
    ; but consists of 1200 bytes
    ; all of which are 20h

msg11:
    db ' '
    db 01ah

msg18: db 0,01ah ;hscr param
    ; 320x240 bonsai tree graphic
    ; The following table is not listed
    ; here. It consists of 9600 bytes
    ; which constitute a full screen
    ; bit map image of a bonsai tree.
    ; You may add a few bytes before the
    ; 01ah termination byte for testing
    ; puposes or include a complete
    ; bitmap image

msg12:
    db 01ah

msg13:
    db 0,0,01ah ;set cursor
    ;to text page

msg14:
    db 'HANTRONIX'
    db 0a1h

msg15:
    db 'Crystal Clear and'
    db 0a1h

msg16:
    db 'Visibly Superior'
    db 0a1h

msg17:
    db 'LCD Modules'
    db 0a1h


end