汇编语言8位无符号数运算

;对于三个8位无符号数86H, 34H, 21H,编写S = 86H×34H-21H的程序data segment    num db 86h, 34h, 21h    result dw ?data endscode segmentassume cs:code, ds:data    start:    mov ax, data    mov ds, ax    lea si, num    lea di, result    mov al, [si]    mov bl, [si+1]    mul bl ;bl*al->ax    mov bl, [si+2] ;取第三个操作数    mov bh, 0    sub ax, bx    mov [di], ax ;结果送result    mov ah, 4ch ;选择功能：程序执行终止    int 21h; ;执行程序终止功能code ends    end start