;Program for Example 20-5 to load 3 numbers and compute their sum
.8087
PAGE 	60,132
.MODEL  SMALL
.STACK	32
;----------------------------
	.DATA
	ORG 	00H
X 	DD 9.75
 	ORG 	10H
Y 	DD 13.09375
 	ORG 	20H
Z 	DD 29.0390625
 	ORG 	30H
SUM 	DD 	?
;----------------------------
	.CODE
START 	PROC 	FAR
 	MOV 	AX,@DATA
 	MOV 	DS,AX
 	CALL 	CSUM
 	MOV	AH,4CH
        INT             21H
START 	ENDP
;-----------------------------
CSUM 	PROC 	NEAR
 	FINIT				;initialize 8087 stack
 	FLD 	X			;load X into ST(0)
 	FLD 	Y			;load Y into ST(0)
 	FLD 	Z			;load Z into ST(0)
        FADD    ST(0),ST(1)             ;ST(0) = Y + Z
 	FADD 	ST(0),ST(2)		;ST(0) = X + (Y + Z)
 	FST 	SUM			;store ST(0) in sum
 	RET
CSUM 	ENDP
 	END 	START