Int 25 Fn CDCD  - Stacker - Get Device Driver Address                      [k]

   AX = CDCDh
   DS:BX -> buffer for address (see #2237)
   CX = 0001h
   DX = 0000h

Return: AX = CDCDh if Stacker installed
       DS:BX buffer filled

Note:  not supported by Stacker Anywhere; to obtain the Stacker device
     driver address and to detect drives controlled by all versions
     of Stacker, INT 21/AX=4404h"Stacker" or lookup via the CDS and DPB
     should be preferred (see INT 21/AH=52h)
   Stacker Anywhere does not link its built-in device driver into
     the standard device driver chain, but it can be found via CDS/DPB

See Also: INT 21/AX=4404h"Stacker"

Format of Stacker v2+ driver address buffer:
Offset Size    Description (Table 2237)
 00h   WORD    signature CDCDh
 02h   WORD    ??? 0001h
 04h   DWORD   pointer to Stacker signature at device driver offset 1Ah
         (see #2238)

Format of Stacker v2+ device driver:
Offset Size    Description (Table 2238)
 00h   DWORD   pointer to next driver, offset=FFFFh if last driver
       FFFFh:FFFFh for Stacker Anywhere
 04h   WORD    device attributes (see #1333,#1334)
 06h   WORD    device strategy entry point
 08h   WORD    device interrupt entry point
 0Ah   BYTE    number of subunits (drives) supported by driver
       0 for Stacker Anywhere
 0Bh  7 BYTEs  signature "STAC-CD" for Stacker and Stacker Anywhere
 12h  7 BYTEs  ???
 19h   BYTE    always = 01h ?? (Stacker Anywhere points here)
 1Ah   WORD    signature A55Ah (all other Stacker versions point here)
 1Ch   WORD    Stacker version * 64h
       0C8h = 200, 012Ch = 300, 0190h = 400 (also Stacker Anywhere)
 1Eh   WORD    offset of volume-specific information offset table
       (list of WORDs, one per drive, containing offsets to various
         information)
 20h 56 BYTEs  n/a
 58h   BYTE    volume number, set after INT 21/AX=4404h, INT 21/AX=4408h
       (use to index into volume-specific info offset table,
       should be set to FFh before and tested for change after)
 59h 19 BYTEs  n/a
 6Ch  4 BYTEs  ASCII string "SWAP"
 70h 26 BYTEs  drive mapping table (one byte for each drive A: through Z:)
       (only used for drives swapped by SSWAP.COM; other drives
       compressed by Stacker can be found with the standard device
       driver header signature (see INT 21/AH=52h)
---Stacker 4, Stacker Anywhere---
 8Ah 40    BYTEs   ???
 B2h  4 BYTEs  ASCII string "SWP2"
 B6h 26 BYTEs  drive table ???
 D0h 150 BYTEs ???
166h 60 BYTEs  LZSINFO structure (see #2494 at INT 2F/AX=4A12h)

See Also: #2239,#1332 at INT 21/AH=52h

Format of Stacker boot record:
Offset Size    Description (Table 2239)
1F0h  8 BYTEs  Stacker signature (first byte is CDh)
1F8h   DWORD   pointer to start of Stacker device driver
1FCh   WORD    Stacker volume number
1FEh   WORD    ???

See Also: #2238