IVAL.i2.v = ITVATT( FCOLOR.i1.r, BCOLOR.i1.r, BLINK.i1.r )

	This function will convert color and blink codes into
	a character attribute byte suitable for use with calls to TVMX.  The
	character attribute byte is returned in the high byte of IVAL.  The
	low byte of IVAL is set to zero.  FCOLOR, BCOLOR, and BLINK are
	optional integer arguments which contain the foreground color code,
	background color code, and blink code respectively.  See the description
	of the TVM routine for definitions of these codes and their defaults.
	returns TRUE if the bit is set and FALSE otherwise.  NBIT must be
	an integer bit number ranging from 1 to 32767 with each bit
	being numbered in ascending order from right to left in agreement
	with DEC's bit numbering convention.