Int 21 Fn E9  - Doubledos - Set Timesharing Priority                       [T]

   AH = E9h
   AL = new priority (see #1777)

Return: AL = priority setting if AL=05h on entry

Note:  identical to AH=F9h

See Also: AH=EAh"DoubleDOS",AH=EBh"DoubleDOS",AH=F9h"DoubleDOS"

(Table 1777)
Values for DoubleDOS timesharing priority:
 00h   visible program gets 70%, invisible gets 30% (default)
 01h   visible program gets 50%, invisible gets 50%
 02h   visible program gets 30%, invisible gets 70%
 03h   Top program gets 70%, bottom program gets 30%
 04h   Top program gets 30%, bottom program gets 70%
 05h   get current priority