;***********************************************************
;Name: 		Addressing Mode Demo

;Author:	Dan Kohn

;Date:		9/12/02

;Function:	To demonstrate the various addressing modes
;		of the 80x86 processor

;On call:	(Self contained code, no inputs needed)

;Returns:	(no Return -> mainline program)

;***********************************************************	
#make_COM#
; COM file is loaded at CS:0100h
; (the value of CS is set by Operating System)
ORG 100h

	jmp main

TEST1 	db	'Dello world how are you'
;    ^ NO : (it will not work with colon)     


main:	mov al,'h'		; Immediate addressing
				; puts 'h' into al

	mov bl,al		; register addressing
				; puts what was in AL into BL
	
	mov al, test1		; direct (from memory)
				; puts the first character of string
				; into AL
	
	mov test1, bl		; direct (to memory)
				; puts what is in BL into memory location
				; pointed to by test1
	
	mov si, offset test1	; Register Indirect (gets what is pointed
	mov al,[si]		; to by label test1 and places that into AL)
				; [valid registers for mode: BX BP SI DI]
				
	mov bx, offset test1	; base address (gets address of TEST1 and adds
	mov al,[bx+2]		; 2 to it and then gets what that is pointing
				; to and places that into AL)
				; [valid registers for mode: BX BP]
	
	mov bp, offset test1	; Base indexed addressing (Gets address of TEST1
	mov si,00007h		; adds the value of BP (7 in this case) and go to 
	mov dl,[si+bp]		; that memory location and put the contents 
				; into DL).
				; [valid registers for mode: BX or BP / DI or SI]
	
	mov bp, offset test1	; Base indexed with displacement (Gets address 
	mov si,00007h		; of TEST1 adds the value of BP (7 in this  
	mov dl,[si+bp+4]	; case) adds the value of 4 and go to that 
				; memory location and puts the contents into DL. 
				; [valid registers for mode: BX or BP / DI or SI]

	hlt