* disk	start	length	stop 	defined	logical
* ===	=====	====== 	====	======= =======
* 191
* 	    1        1     1    IVPM1	191
* 	    2        1     2    IVPM2	191
* 	    3        5     7    RSCS	191
* 	    8	     5 	  12	OPERATOR 191
* 	   13        4    16	CE	191
*	   17        7    23    MAINT	191
*	   24        5    28    ECMODE	191
*	   29        1    29	MAINT	199
*	   30       85	 114	MAINT	190
*	  115	    27   141	MAINT	194
*	  142	   666   807	unused