ex3_6.asm

	; string lower case to higer case
data segment
capacity	equ		100
buffer		db		capacity	
			db		0			; return length
			db		capacity dup(0)
data ends

stack1	segment para stack
			dw	10h		dup(0)
stack1 ends

codeseg	segment
start:
	assume cs:codeseg, ds:data, ss:stack1
	mov		ax,		data
	mov		ds,		ax
	; get the input string
	mov		dx,		offset buffer
	mov		ah,		0ah
	int 21h
	mov		dl,		0ah
	mov		ah,		02h
	int 21h
	mov		bx,		offset buffer+1
	mov		cl,		[bx]				; Get the length of the string
	xor		ch,		ch
testchar:
	inc		bx
	mov		al,		[bx]				; Get the character
	cmp		al,		'a'
	jb		display
	cmp		al,		'z'
	ja		display
	; It is a lower case character, change it into higer case
	sub		al,		20h
display:
	; ascii of the character is in ax
	mov		dl,		al
	mov		ah,		2
	int 21h
	loop testchar
	; Done
	mov		ah,		4ch
	int 21h

codeseg ends
	end start