DOS buffered input

.model small
.stack 100h
.data
    ; First byte of buffer is number of characters to read (including Carriage Return)
    ; Second byte will be the number of bytes read (not including the Carriage Return).
    buffer db 9, 0, 9 dup("$")

.code
main proc
    mov ax,@data
    mov ds,ax

    LEA dx,buffer             ; Read input. see: http://www.ctyme.com/intr/rb-2563.htm
    mov ah,0Ah
    int 21h

    ; Set BX to index of the Carriage Return in the buffer
    mov bh, 0                 ; Upper part of BX set to 0
    mov bl,[buffer+1]         ; [buffer+1] contains the nu,ber of chars read excluding Carriage Return

    mov [buffer+bx+2], '$'    ; Replace the Carriage Return by a $ (end of string)

    LEA dx,buffer+2           ; Print out the string entered
    mov ah,09h
    int 21h

    LEA dx,buffer+2           ; Print out the string entered
    mov ah,09h
    int 21h

    mov ah,4ch
    int 21h
main endp
end main