AY-3-8500


The AY-3-8500 "Ball & Paddle" integrated circuit was the first in a series of ICs from General Instrument designed for the consumer video game market. These chips output video to an RF modulator, which would then display the game on a domestic television set. It was introduced in 1976, Coleco becoming the first customer, having been introduced to the IC development by Ralph H. Baer. The lineup was later known as the GIMINI series. Approximately 5 million 8500s were sold and used in hundreds of different consoles.
The 8500 contained six selectable games — tennis, hockey, squash, practice, and two shooting games. The 8500 was the 625-line PAL version and the 8500-1 was the 525-line NTSC version. A minimum number of external components were needed to build a complete system. The video was in black-and-white, although it was possible to colorize the game by using an additional chip, the AY-3-8515.
The 8500 was later updated with the AY-3-8550, which used formerly unused pins on the 8500 to add two-axis control with a joystick instead of the more typical single-axis control with a paddle. It was otherwise similar and played the same games, and could also be used with the 8515 for color support. The AY-3-8610, also known as the "Superstar", added several new games and required the new AY-3-8615 for color support.
As the games console market moved to ROM cartridges in the late 1970s, GI introduced the AY-3-8900, a separate video display controller intended to be used with their own CP1610 microprocessor. Although entirely different than the 8500 line, they were also considered part of the GIMINI lineup.

History

The 8500 development was led by GI's Stephen Maine, working with Eric Berman and Duncan Harrower. Harrower had begun working on the concept in 1974. The system was announced in December 1975 and began shipping early the next year. Coleco was the first customer, with Radio Shack and Magnavox following. Ultimately it was used by "hundreds of different games systems" around the world, and over 5 million were sold in 1976 alone.
The company continued development of the 8500 series, introducing new dedicated games chips. However, as they noted, "dedicated television game chips consumed huge resources to develop", a problem also noted by competitor Atari at the same time. Both companies began developing new second-generation systems, using a general purpose central processing unit to handle logic, and a dedicated video display unit to produce the graphics.

AY-3-8500

Games

Six selectable games for one or two players were included:
In addition, a seventh undocumented game could be played when none of the previous six was selected: Handicap, a hockey variant where the player on the right has a third paddle. This game was implemented on very few systems.

Usage

The AY-3-8500 was designed to be powered by six 1.5 V cells. Its specified operation is at 6-7 V and a maximum of 12 V instead of the 5 V standard for logic. The nominal clock was 2.0 MHz, yielding a 500 ns pixel width. One way to generate such a clock is to divide a 14.31818 MHz 4 × colorburst clock by 7, producing 2.04545 MHz. It featured independent video outputs for left player, right player, ball, and playground+counter, that were summed using resistors, allowing designers to use a different luminance for each one. It was housed in a standard 28-pin DIP. The image could be colorized using the AY-3-8515 chip, which converted luminance values to pre-selected colors.

Applications

Some of the dedicated consoles employing the AY-3-8500 :

AY-3-8550

The AY-3-8550 was the next chip released by General Instruments. It featured horizontal player motion, and a composite video output. It was pin compatible with the AY-3-8500. It needed an additional AY-3-8515 chip to output video in color.

Games

Six selectable games for one or two players were included:

Usage

The AY-3-8550 used the No Connect pins from the AY-3-8500, so it was possible to put an AY-3-8550 on an AY-3-8500, and vice versa.

Application

This is a list of consoles that use this chip:

AY-3-8610

The AY-3-8610 was a major update from General Instruments. It played more games, like basketball or hockey, with higher-quality graphics. It was nicknamed "Superstar" by GI. It was in black and white, although it was possible to add color by using an additional AY-3-8615 chip.
Prior to producing the 8610, GI created the AY-3-8600. The pin configuration was the same as the 8610, but it was missing the two rifle/target games, bringing the total number of games down to 8.

Games

The 10 selectable games for this chip included:
GameNo. of
players
Tennis2
Hockey/Soccer2
Squash2
Practice1
Gridball1
Basketball2
Basketball practice1
Two player target2
Single player target1

Usage

The AY-3-8610 featured a completely different pinout. It, too, required an external crystal oscillator. It still had separate video output pins, and removed the dedicated sync pin.

Application

This is a list of consoles that use the AY-3-8610:
Some consoles that use the AY-3-8600 chip:

Derivatives

chipYearDerived fromDIPConsoleNote
AY-3-85101978AY-3-850016 pinColeco Telstar ColortronFour of six games of 8500, with full colors
AY-3-8512197?AY-3-850016 pinColeco Telstar MarksmanThe same as 8500 but with colors
AY-3-8700
AY-3-8710		197828 pinColeco Telstar Combat!
PC-50x		Four combat games with tanks, 2 players
AY-3-86031978PC-50xCar race with vertical view. The car accelerate and the player must avoid collisions. 1 or 2 players
AY-3-86051978PC-50xThree games: a ship must fire torpedoes to hit submarines
AY-3-86061978PC-50x10 breakout games. 1 or 2 players
AY-3-8760
1978Atari Stunt Cycle
Sears Motocross
PC-50x		Motor-Cycle. Three game levels. A motorbike must jump over different objects
AY-3-86071978PC-50x4 games with an optical rifle. More than one difficult level
AY-3-87501978Superspace. Space battle for two players

  • An equivalent to the AY-3-8500 is the TMS1965NLA manufactured by Texas Instruments.
  • The Soviet K145IK17 has a built-in counter, making it possible to use a momentary pushbutton instead of a multi-position switch to select games. The handicap game is not hidden, it can be chosen among others using this button. Since a pushbutton occupies only one pin, this IC has fewer pins.
  • A competitor was the National Semiconductor MM57105.