The Standard Television Interface Chip[1] or STIC is a video encoder chip produced by General Instrument as AY-3-8900/AY-3-8900-1 and used on the Mattel Intellivision.
[2][3][4][5] The chip provides all the display functions on the machine, and works as an internal timer.
[6] Other objects, such as a 20 × 12 matrix of 8×8 background cards can be used to create scenery or provide game information.
The STIC also computes collision information between the objects and screen borders.
Actual tones varied according to the analog television standard and quality of the CRT display.