Function 62h Get PSP Address DOS 3.0+
Returns the segment address of the program segment prefix (PSP)
for the current program.
Entry AH = 62h
Return BX = Segment address of PSP
Note
Functions 51h and 62h are identical. Programs can use either
to get the segment address of the current PSP.
Function 51h (undocumented until DOS 5.0 was released) is
supported by DOS 2.0+, function 62h by DOS 3.0+.