; PROGRAM TO DEMONSTRATE BCD (BINARY CODED DECIMAL).
; 9h IN HEX IS 9 DECIMAL. 
; Ah IN HEX IS 10 DECIMAL. 
; IF WE WANT TO SHOW A HEX VALUE LIKE Ah BUT IN B.C.D., WE WILL NEED TO ADD 6 TO IT.
; EXAMPLES:
; Ah + 6h = 10h. 
; Bh + 6h = 11H
; Ch + 6h = 12h
; Dh + 6h = 13h
; Eh + 6h = 14h
; Fh + 6h = 15h
;
.ORG 0000h					; CHANGE ON REASSEMBLY.

START:	LD	DE,	0			; D=BCD, E=BINARY.
		LD	IX,	0030h		; BCD BUFFER (30h TO 93h).
		LD	IY,	00A0h		; BINARY BUFFER (A0h TO 103h).
		LD	B,	100			; COUNT.
LOOP:	LD	(IX +0),	D	; STORE BCD.
		LD	(IY +0),	E	; STORE BINARY.
		INC	IX				; BUMP BCD POINTER.
		INC IY				; BUMP BINARY POINTER.
		LD	A,	D			; GET BCD.
		ADD	A,	1			; ADD 1.
		DAA					; DECIMAL ADJUST. IF ANY DIGIT VALUE IS NOT BETWEEN A AND F, THEN DAA DOES NOTHING.
		LD	D,	A			; SAVE BCD VALUE.
		LD	A,	E			; GET BINARY .
		ADD	A,	1			; ADD 1.	
		LD	E,	A			; SAVE BINARY VALUE.
		DJNZ	LOOP		; LOOP IF NOT 100.
; LOOP1:	JR	LOOP1		; LOOP HERE IF DONE.
		HALT
					
.END