ext28     headr
     TOPCD9    equ  840   TOP OF CODE & 5 & X00 - 1
     DIFF16    equ  846   16 * (BOTTAB - 1 - TOPCD9)
     BNDRY     equ  849   TOPCD9 + 0.48 * (BOTTAB - 1 - TOPCD9)
     BOTTAB    equ  852   BOTTOM OF TABLES
     MOVEDN    equ  853   
     BEGN28    equ  937   TOP OF CODE