INT 2F - PCED/KEYDEF - INSTALLATION CHECK                                       
	AX = 48C3h
	BL = 00h
Return: AX = 0000h if installed
	    BX = KEYDEF resident segment
Program: KEYDEF is a resident keyboard redefinition utility included as part
	  of the PCED package by Cove Software
Note:	chains if BL <> 00h on entry
SeeAlso: AX=48C0h,AX=48C2h,AX=48C4h