Page:Gametronics Proceedings.djvu/189

 MG104 best answered the problem. The decision to use this test was made because of the speed at which it was capable of operating, its cost, the simplicity of programming it, and also because of the willingness of this company to work with us on a round-the-clock crash basis to provide us with the initial testers we needed to meet the demand for the game chips.

We needed about 30 test stations, all operating at 2 MHz, to test the devices. Although some equipment that could run at this speed and do the job required was selling for up to $150,000 per unit, we were able to purchase the testers for $25,000 to $30,000 each.

We found about ten test stations in house that we could use and bought 20 testers to meet the requirements for test stations.

We found that the test equipment could be brought on line. Testing was begun with actual operation of the game on the TV monitor. Fortunately, the performance of the IC could be observed on the television screen using special test exercising apparatus.

Skilled observers became so adept at exercising the game chips that malfunctions could often be correctly attributed to a particular transistor on the chip.

The AY38500 offered game designers many features including six selectable games –– tennis, soccer, squash, practice, all ball-and-paddle games, and two rifle-shooting games.

The chip provides automatic scoring and character generation on the chip for displaying two scores from zero to fifteen on the screen. The bat sizes are selectable externally, using switches. The angles are also selectable externally by switches as is the speed of the ball. Ball service can be automatic or manual after a score takes place as desired by the players.

One of the main features of the chip was that it was very easy to use. It was self-contained with scoring, character generation, very simple sound interfacing and simple bat controls –– each a potentiometer and a capacitor. It used only 30 milliamperes, offering designers a rechargeable battery-powered option.

The chip also made it possible for manufacturers to produce games that differed from one another. Many manufacturers did not use all of the selectable features in order to keep costs down.

To support customers for the game chip. General Instrument also developed the external circuitry needed to use the chip in a game system; this included oscillators, speaker drivers and modulators.