《IBM-PC汇编语言程序设计第二版》部分习题答案(第5章).doc

5.1 试编写一个汇编语言程序，要求对键盘输入的小写字母用大写字母显示出来.model small.stack 100H.codemain proc farStart:?push dx?mov ax,0?push ax??mov ah,01H?int 21H??cmp al,61H??jl lop1??cmp al,7BH?jge lop1??sub al,20H?mov dl,al??lop1:mov ah,2?int 21H??retEnd start 5.2 编写一个程序，从键盘接受一个小写字母，然后找出它的前导字符和后续字符，再按顺序显示这三个字符..model small.386.codeMAIN PROC FARstart:?push ds?sub ax,ax?push ax?input:?mov ah,7H?int 21Hcmpe:??cmp al,20H?JE? exit??cmp al,61H?JL? input??cmp al,7AH?JG? inputprint:?sub al,01H?mov dl,al?mov ah,02H?int 21H??add al,01H?mov dl,al?mov ah,02H?int 21H??add al,01H?mov dl,al?mov ah,02H?int 21H??;输出换行回车?mov dl,0AH?mov ah,02H?int 21H ?jmp inputexit :?retMAIN ENDPEND start 5.3 将AX寄存器中的16位数分成4组，每组4位，然后把这四组数分别放在AL、BL、CL、DL中。.model small.datax DB 4 dup(?).stack 100H.codeMAIN PROC FARstart:?push ds?and ax,00H?push ax??mov ax,1234H??mov cx,04H?mov si,00Hlop:?push cx?mov? cl,04H?rol ax,cl?push ax?and al,0FH?mov BYTE PTR x[si],al?pop ax?pop cx?add si,2?Loop lop?mov al,[X]?mov bl,[X+2]?mov cl,[X+4]?mov dl,[X+6]print:?mov ah,02H?int 21H??mov dl,al?mov ah,02H?int 21H??mov dl,bl?mov ah,02H?int 21H ?mov dl,cl?mov ah,02H?int 21Hexit:?retMAIN ENDPEND start 5.4 编写一个程序，要求比较两个字符串STRING1和STRING2所含字符是否相同，若相同则显示MATCH，若不同在显示:NO MATCH。 .model small.dataSTRING1 DB I must study hardSTRING2 DB I must study hardX?????? DB MATCH .$Y?????? DB NO MATCH.$ .stack 100H.codemain proc farStart:?push dx?mov ax,0?push ax??mov ax,@data?mov ds,ax?mov es,ax??lea si,STRING1?lea di,STRING2?cld??mov cx,(string2-string1)/ type STRING2?retEnd start 5.5编写一个程序，要求能从键盘接收一个个位数N，然后响铃N次，（响铃的ASCII为07）。这题比较有意思，呵呵。model small .codemain proc farstart:?push ds?sub ax,ax?push axinput:????牋牋 mov ah,01H牋牋牋牋 int 21H 牋牋牋牋 cmp al,20H牋牋牋牋 je?exit 牋牋牋牋 cmp al,30H牋牋牋牋 jle input牋牋牋牋 cmp al,3AH牋牋牋牋 jge input牋牋牋牋 sub al,30H牋牋牋牋 mov cx,ax牋牋牋牋 and cx,0FFHlop:牋牋牋牋 mov dl,07H牋牋牋牋 mov ah,2H牋?