DEF  WRITE,READ
       REF  STRREF,STRASG,VSBW
WRITE  LI   R3,>2222
       LI   R4,>6000
LL     MOV  R3,*R4+
       CI   R4,>8000
       JNE  LL
       RT
READ   CLR  R0
       LI   R1,1
       LI   R2,>6FF8
       LI   R5,>0F00
       MOVB R5,@>6FF8
       BLWP @STRASG
       RT
       END
       MOVB R5,@>6FF8