从汇编中的键盘读取缓冲区

Question

我需要使用缓冲区从键盘读取字符串。

在示例和文献的帮助下，我设法编写了这段代码，但是当我尝试打印出我插入的字符串时，它只给我消息 "Input your string again:".

我应该在我的代码中更改什么，以便打印我插入的内容？

.model small

stack 100h

.data

    ;reading buffer
    buffSize DB 255       ;Number of maximum characters than can be read
    read DB ?             ;Number of characters that was read
    buffer  DB 255 dup (?) ;Read characters are placed here

    ;Other data
    input DB "Input your string: $",13,10
.code

Start:

    MOV ax,@data
    MOV ds,ax

    MOV ah,9
    MOV dx, OFFSET input
    INT 21h                     ;Prints input string

    MOV ah, 0Ah
    MOV dx, OFFSET buffSize
    INT 21h                     ;Text is read

    MOV bx, OFFSET buffer       ;Address of buffer is inserted to bx
    MOV cl, read                ;Content of read is inserted to cl
    MOV ch, 0                   ;In cl there is a number of inserted characters

    MOV byte ptr [ds:bx], '$'

    MOV ah, 9
    MOV dx, OFFSET buffer
    INT 21h

    MOV ah,4Ch
    INT 21h
END Start

Answer 1

input DB "Input your string: "
nextLine db "$",13,10

nextLine 作用不大。把“$”放在后面13,10.
最好也把输入文本划在同一行.

input    db "Input your string: $"
nextLine db 13,10,"$"

buffSize DB 255       ;Number of maximum characters than can be read
read DB ?             ;Number of characters that was read
buffer  DB 25 dup (?) ;Read characters are placed here

如果允许输入255个字符，还应该定义一个足够大的缓冲区！ 25 dup (?) 比规定的 255 尺寸小得多。

要重新打印输入，在文本后面放一个$：

mov  bx, OFFSET buffer     ;Start of the text
add  bl, read              ; plus the number of characters in the text
adc  bh, 0                 ;Maybe there was a carry from previous addition!
mov  byte ptr [bx], "$"    ;DOS needs string $-terminated
mov  ah, 09h               ;DOS.DisplayString
mov  dx, OFFSET buffer
int  21h

Answer 2

您已将“$”放在缓冲区的开头。尝试

    mov di, cx
    mov [bx+di], '$'

从汇编中的键盘读取缓冲区

Read buffer from keyboard in Assembly

assembly

buffer

dos

dosbox

x86-16