INT 18 - NEC PC-9800 series - VIDEO                                             
	AH = function
	    0Ah set video mode
	    0Bh get video mode
	    0Ch start text screen display
	    0Dh end text screen display
	    0Eh set single display area
	    0Fh set multiple display area
	    10h set cursor shape
	    11h display cursor
	    12h terminate cursor
	    13h set cursor position
	    14h read font patter
	    16h initialize text video RAM(Random Access Memory)	See also DRAM, SRAM.
	    1Ah define user character
	    others
	???
Return: ???
Notes:	details are not available at this time
	text video RAM(Random Access Memory)	See also DRAM, SRAM. is located at segments A000h (characters) and A200h
	  (attributes), graphics video RAM(Random Access Memory)	See also DRAM, SRAM. at segment C000h


Bitfields for NEC PC-9800 series video attributes:
Bit(s)	Description	(Table 00648)
 0	disable drawing character
 1	blinking
 2	reverse video
 3	underline
 4	vertical line
 7-5	color
	(0=black, 1=blue, 2=red, 3=purple, 4=green, 5=cyan, 6=yellow, 7=white)