Int 2F Fn 7200  - Srdisk V1.30 - Installation Check                        [d]

   AX = 7200h

Return: AL = FFh if installed
       ES = segment of device driver header (see below)
Program: SRDISK is a freeware resizeable RAMdisk by Marko Kohtala

Format of device driver header:
Offset Size    Description
 00h 10 BYTEs  same as standard device driver header (see INT 21/AH=52h)
 0Ah   BYTE    number of subunits (drives) supported by driver
 0Bh  3 BYTEs  signature "SRD"
 0Eh  4 BYTEs  memory type string (currently only "XMS ")
 12h  4 BYTEs  ASCII driver version string "N.NN"
 16h   BYTE    00h
 17h   BYTE    configuration format version (currently 00h)
 18h   WORD    offset of drive configuration data