 According to Joe Decuir, George McLeod designed the CTIA in 1977.The CTIA chip was replaced with the Graphic Television Interface Adaptor (GTIA) in later revisions of the 400 and 800 and all other members of the Atari 8-bit family.GTIA, also designed by George McLeod, adds three new color interpretation modes for ANTIC's Playfield graphics that enables the display of more colors on the screen than previously available.