INT 49 - TI Professional PCIBM PC - CRT - FILL ENTIRE SCREEN WITH ATTRIBUTE
	AH = 12h
	AL = attribute (see #03210)
Return: nothing
Note:	AH=00h,04h,05h,0Bh,0Ch,0Dh,0Fh are documented as NOPs
SeeAlso: AH=01h,AH=02h


Bitfields for TI Professional PCIBM PC screen attribute:
Bit(s)	Description	(Table 03210)
 7	alternate character set (requires user-supplied ROM(Read-Only Memory) A memory for program storage which may not be changed by the program as it runs.)
 6	blink
 5	underline
 4	reverse video
 3	character enable
 2	green (color) or 58% intensity (gray-scale)
 1	red (color)  or 27.5% intensity
 0	blue (color) or 14.5% intensity