汇编程序：1、编程计算S=1+3+5+......+99,并以十六进制形式显示S的值

汇编程序：1、编程计算S=1+3+5+......+99,并以十六进制形式显示S的值

;1+3+....+99=(1+99)*50/2=9C4
CODE SEGMENT
ASSUME CS:CODE
START: MOV CX,99
MOV AX,0
LOP: ADD AX,CX
SUB CX,2
JNS LOP
MOV BX,AX
CALL DISPLAY
MOV AH,4CH
INT 21H
;入口参数：BX
;功能：显示字数据
DISPLAY PROC
PUSH CX
MOV CH,4
MOV CL,4
LOP1: ROL BX,CL
MOV DL,BL
AND DL,0FH
ADD DL,30H
CMP DL,3AH
JB NEXT
ADD DL,7
NEXT: MOV AH,2
INT 21H
DEC CH
CMP CH,0
JNZ LOP1
POP CX
RET
DISPLAY ENDP
CODE ENDS
END START

.386
STACK SEGMENT USE16 STACK
DB 2000 DUP(0)
STACK ENDS

DATA SEGMENT USE16
NUM DD 99
OUTPUT DB 0DH,0AH,'SUM 0F 1 .. 8000 IS : '
RESULT DB 16 DUP (' '),'$'
DATA ENDS

CODE SEGMENT USE16
ASSUME CS:CODE,DS:DATA,SS:STACK
START:
MOV AX, DATA
MOV DS, AX
MOV EBX, NUM
PUSH EBX
CALL SUM_P ;计算1....8000的和 结果在EAX中
CALL F2T10 ; (EAX) 转化为十进制可显示字符放到 result 缓冲区中
LEA DX, OUTPUT
MOV AH, 9
INT 21H
EXIT: MOV AH,4CH
INT 21H

SUM_P PROC
MOV BP,SP
MOV EBX, [BP+2]
MOV EAX,0
LP: ADD EAX,EBX
DEC EBX
cmp EbX, 0
JNZ LP
RET 4
SUM_P ENDP

; 将 (EAX) 中的内容，转换成 十进制数串
F2T10 PROC
MOV EBX, 10
LEA SI, RESULT+15
L1: MOV EDX, 0
DIV EBX
ADD DL,30H
MOV [SI],DL
DEC SI
CMP EAX, 0
JZ F_EXIT
JMP L1
F_EXIT:
RET
F2T10 ENDP

CODE ENDS
END START