Programming - Once again about interruptions.

********** ABOUT INTERRUPTIONS AGAIN **********
(HOW NOT TO DISTURB THE INFORMATION BALANCE)
                                           
   ALMOST ALL TIME MW AND ALL MW APPLICATIONS
OPERATE IN INTERRUPTION MODE 2 (IM 2). THAT
IT DOES NOT NEED TO APPLY ANYTHING TO INSTALL IT
SPECIAL EFFORT, YOU ONLY NEED TO CALL THE PROGRAM
INITZ FRAME WHICH WILL SET STANDARD
IM 2 HANDLER (MW HANDLER), FINDING-
AVAILABLE AT ADDRESS #E99B. MUST CALL
THIS HANDLER IS 50 TIMES PER SECOND (EXACTLY
THIS IS WHAT THE INTERRUPTION MODE DOES 2) SO THAT
THE MOUSE WORKED NORMALLY (CURSOR, THAT IS).
   IN ADDITION, IN MODE 2 YOU CAN WITHOUT DANGEROUS
DO NOT USE THE IY REGISTER FOR YOUR OWN PURPOSES.
IN MWL IY IS USED AS A WINDOW DESCRIBER AND
FOR OTHER PURPOSES (ALTHOUGH MWL ITSELF DOESN'T PROVIDE
APPEALS TO ROM SUBROUTINES, WHICH FOR
ADDRESSING SYSTEM VARIABLES ROM USES
USE REGISTER IY YOU MAY NEED
SUCH TREATMENT. IN SUCH CASE DON'T FORGET-
TE INSTALL - LD IY,#5C3A ! ) .      
   NEVER WORK WITH THE DISK IN
IM MODE 2 (ALTHOUGH, DRIVER AND DRIVER+ YOU
YOU CAN ALSO USE IN INTERRUPTION MODE 2 -
NII, T.K. THEY ARE VERY CUTTERLY WRITTEN
PODINO LARCHENKO, AND A LITTLE ADDED
BY ME), T.K. WHEN WORKING WITH A DISK, YOU MUST
MAY SWITCH TO 0 INTERRUPTION MODE.   
   EXAMPLE:...PROGRAM... DISK LD HL,30000
............... LD DE,0    
 LD IY,#5C3A LD BC,#0805
 IM 0 CALL 15635   
 CALL DISK RET          
 CALL INITZ                                
                                           
   NOTE: IN LATER VERSIONS MW
(SORRY NOT IN THE FIRST BUT MOST LIKELY
ALREADY WITH THE SECOND! ) THIS IS AN ANNOYING INCONVENIENCE,
CAUSED BY TR-DOS ARCHITECTURE) WILL BE SET-
WOUNDED AND THE DISK CAN BE WORKED WITH,
WITHOUT CHANGING THE INTERRUPTION MODE. :)          
   YES, BY THE WAY: WHEN GOING TO BASIC IT’S THE SAME
IT IS NECESSARY TO SET MODE IM 0, BUT ABOUT
THIS IS IN THE NEXT CHAPTER...