INT 27h (39)             Terminate and Stay Resident

Terminates a program and leaves a specified portion installed in
memory.

On entry:      CS         Segment of PSP
DX         Address at which next program may be loaded
(i.e., highest address to stay resident + 1)

                                                                          

Note:          Interrupt 27h is the original (i.e. DOS 1.x) method
of creating a TSR program. Unlike its DOS 2.0-and-
later counterpart, Interrupt 21h, Function 31h, it
does not allow you to pass a return code. And the
amount of memory that may kept resident is limited
to 64K.

Use INT 21h function 31h to keep EXE programs
resident in memory.

Files are not closed by Interrupt 27h.

See also: 31h
See also: 00h
See also: INT 20h
See also: 4Ch

INT 27h (39) Terminate and Stay Resident