K0100:

MOV     AH,00
MOV     AL,03  ;DEFAULT = 3 -25x80 TEXT
MOV     DL,[005D]  ;TAIL VALUE
CMP     DL,30  ;LESS THAN 0 ?
JB      K0117
                               
CMP     DL,38  ;GREATER THAN 8 ?
JNB     K0117

SUB     DL,30
MOV     AL,DL

K0117:

INT     10

MOV     AH,4C  ;RETURN TO DOS
INT     21
INT     20