INT 64 - Extended Batch Language v3.14+                                         
	AH = function
	    00h to 5Fh chained to previous handler
	    60h to 6Ch reserved, return immediately
	    80h to FFh chained to previous handler
	    6Dh (v4.01+) insert tone in queue
		AL = ???
		CX = frequency in Hertz
		DL = duration in clock ticks
		Return: AL = 00h if note stored
			   = 01h if no room to store
	    6Eh clear ??? counter/flag
	    6Fh return counter/flag that AH=6Eh clears
	    70h ???
		AL = ???
	    71h ???
		AL = ???
	    72h ???
	    73h insert byte at end of keyboard buffer
		AL = byte to insert
		Return: AL = 00h if byte inserted
			   = 01h if no room to store
	    74h insert byte at front of keyboard buffer
		AL = byte to insert
		Return: AL = 00h if byte inserted
			   = 01h if no room to store
	    75h ???
	    76h get keyboard "stack" status
		AL = 'K' if kbd read will read physical keyboard
		     'S' if it will read EBL internal keyboard buffer
		AH = ???
	    77h clear internal keyboard buffer
	    78h ???
		AL = ???
	    79h ???
	    7Ah ???
		AL = ???
	    7Bh ???
		AL = ???
	    7Ch ???
		AL = ???
	    7Dh ???
		AL = ???
	    7Eh clear buffer for ???
	    7Fh installation check
		Return: CX = version in BCD(Binary Coded Decimal) A method of data storage where two decimal digits are stored in each byte, one in the upper four bits and the other in the lower four bits.  Since only the values 0 through 9 are used in each half of a byte, BCD values can be read as decimal numbers on a hexadecimal display of memory or a file.
			DI = segment of ???
			BX = segment of next program's PSPsee Program Segment Prefix???
Program: Extended Batch Language is a batch-file enhancer by Seaware
Notes:	the chaining does not check whether the interrupt had been hooked
	  before, so if you try to chain when the previous vector was
	  0000h:0000h, you'll be in trouble
	functions 72h and 7Ah-7Dh appear to be interfaces to the optional
	  floating-point and extended function packages
Index:	installation check;EBL|installation check;Extended Batch Language