Format of KEYB internal data:
Offset	Size	Description	)
 00h	DWORD	original INT 09
 04h	DWORD	original INT 2F
 08h	DWORD	unused (0) original INT 16 in older KEYB versions???
 0Ch	WORD	flags A (see #02973)
 0Eh	WORD	flags B (see #02974)
 10h	BYTE	flags??? (bit1 used)
 11h	BYTE	???
 12h  4 BYTEs	???
 16h  2 BYTEs	country ID letters, default is "US"
 18h	WORD	current code page (see #01757 at INT 21/AX=6602h)
---DOS 3.3---
 1Ah	WORD	pointer to first item in list of code page tables???
 1Ch	WORD	pointer to ??? item in list of code page tables
 1Eh  2 BYTEs	unused???
 20h	WORD	pointer to key translation data (see #02976)
 22h	WORD	pointer to last item in code page table list (see #02975)
 24h  9 BYTEs	???
---DOS 4.01---
 1Ah  2 BYTEs	???
 1Ch	WORD	pointer to first item in list of code page tables???
 1Eh	WORD	pointer to ??? item in list of code page tables
 20h 2 BYTEs	unused???
 22h	WORD	pointer to key translation data (see #02976)
 24h	WORD	pointer to last item in code page table list (see #02975)
 26h  9 BYTEs	???
---DOS 6.22--- (checked out with 6.22, but might be earlier)
 1Ah  2 BYTEs	???
 1Ch	WORD	pointer to current (first???) item in list of code page tables
		(corresponding to codepage indicated at offset 18h)
		(initial value is FFFFh)
 1Eh	WORD	pointer to (entry to) list of code page tables (see #02975)
		If not FFFFh, INT 2F/AX=AD81h scans this list of code page
		  tables until the requested code page was found in list or
		  end of table was reached (FFFFh). If found, offsets 18h and
		  1Ch will be changed to requested new code page. If not found,
		  it returns with AX=0001h 'code page not supported').
 20h	WORD	unused??? (initial value: FFFFh)
 22h	WORD	pointer to key translation data (see #02455)
 24h	WORD	pointer to last item in code page table list (see #02454)
 26h	WORD	CAPSLock/ShiftLock management flags??? (0)
		Note:	It appears that none of the bits is ever set inside
			  KEYBs code!
			  The following is guesswork:
		bit15: =1: With country specific keyboard mapping (<Ctrl>+
			  <Alt>+<F2>) active, <CapsLock> works as CAPSLock
			  instead of ShiftLock??? Pressing a key in first row
			  resets CapsLock???
			  (Effective only on PC Convertible or with Enhanced
			  keyboard).
		bit14-10:  unused (0)
		bit 9: =1: With country specific keyboard mapping active:
			  some kind of temporary (table) shift???
		bit 8-0: unused (0)
 28h	BYTE	unused (0)
 29h	BYTE	make code xx for <Ctrl>+<Alt>+<xx> to set keyboard mapping
		  to US-layout (default is 3Bh=<F1>???)
		  (see INT 2F/AX=AD82h,INT 2F/AX=AD83h)
 2Ah	BYTE	make code yy for <Ctrl>+<Alt>+<yy> to set keyboard mapping
		  to country specific layout (default is 3Ch=<F2>???),
		  (see INT 2F/AX=AD82h,INT 2F/AX=AD83h)
 2Bh 16 BYTEs	unused (0) ???
Note:	at least in MS-DOS v6.22, the signature "SHARED DATA" immediately
	  precedes this structure