read_string:
    call newline
    mov si, read_attempt
    call print
    call newline
    push bx
    mov ah, 0x03
    int 0x10
    mov dl, 0
    int 0x10
                    ;read 1st char
    mov ah, 0x08
    int 0x10
    mov bl, al
    pop bx
                    ;read 2nd char
    mov ah, 0x03
    int 0x10
    add dl, 1
    int 0x10
    mov ah, 0x08
    int 0x10
    mov bl, al
    pop bx
                    ;read 3rd char
    mov ah, 0x03
    int 0x10
    add dl, 1
    int 0x10
    mov ah, 0x08
    int 0x10
    mov bl, al
    pop bx
                    ;try to write all 3 chars
    call newline
    mov si, write_attempt
    call print
    call newline
    push bx
    mov al, bl
    call printchar
    push bx
    mov al, bl
    call printchar
    push bx
    mov al, bl
    call printchar
    call newline
    mov si, read_write_success
    call print
    call newline
    ret