;solution for Example 13-6
		MOV	AL,0B6H		;control byte:counter2,lsb,msb,binary 
		OUT	43H,AL		;send the control byte to control reg	
;load the counter2 value for D3 and play it for 250 ms	
                MOV     AX,1FB4H        ;for D3 note 
OUT 	42H,AL		;the low byte
		MOV 	AL,AH		
		OUT 	42H,AL		;the high byte
;turn the speaker on
		IN	AL,61H		;get the current setting of port b
                MOV     AH,AL           ;save it
                OR      AL,00000011B    ;make pb0 =1 and pb1 =1
		OUT 	61H,AL		;turn the speaker on
		CALL 	DELAY		;play this note for 250 ms
                MOV     AL,AH           ;get the original setting of port b
		OUT 	61H,AL		;turn off the speaker
                CALL    DELAY_OFF       ;speaker off for this duration
;load the counter2 value for A3 and play it for 500 ms
                MOV     AX,152FH        ;for A3 note
		OUT 	42H,AL		;the low byte
		MOV 	AL,AH		
		OUT 	42H,AL		;the high byte
;turn the speaker on			
		IN 	AL,61H		;get the current setting of port b
                MOV     AH,AL           ;save it
                OR      AL,00000011B    ;make PB0 =1 and PB1 =1
		OUT 	61H,AL		;turn the speaker on
		CALL 	DELAY		;play for 250 ms
		CALL 	DELAY		;play for another 250 ms
                MOV     AL,AH           ;get the original setting of port b
		OUT 	61H,AL		;turn off the speaker
                CALL    DELAY_OFF       ;speaker off for this duration
;load the counter2 value for A4 and play it for 500 ms
                MOV     AX,0A97H        ;for A4 note 
		OUT 	42H,AL		;the low byte
		MOV 	AL,AH		
		OUT 	42H,AL		;the high byte
;turn the speaker on	
		IN 	AL,61H		;get the current setting of port b
                MOV     AH,AL           ;save it
                OR      AL,00000011B    ;make PB0 =1 and PB1 =1
		OUT 	61H,AL		;turn the speaker on
		CALL 	DELAY		;play for 250 ms
                MOV     AL,AH           ;get the original setting of port b
		OUT 	61H,AL		;turn off the speaker
                CALL    DELAY_OFF       ;speaker off for this duration