GI-AY-3-8500 User guide

About the chip

The AY-3-8500 was a pong-on-a-chip system produced from 1975 to the early '80s. It could play five PONG-like games and two shooting games (If a rifle circuit was installed.) It has 0-15 on-screen scoring, and options such as variable bat size, ball speed, and rebound angles. This particular chip is an NTSC variant produced in 1976.

Simulation Controls

The control buttons are on the upper-right of the screen. The function as follows:

• Play/Pause simulation

• Reset simulation

• Step Back (a half clock pulse)

• Step Forward (a half clock pulse)

• Generate (about) one line

• Generate (about) one field (Warning, may freeze the simulation/browser for several seconds)

To increase the speed of the simulation, disable the redrawing with the "Animate during simulation" check-box (below model)

Visual Model

The visual model shows the chip's wiring and logic states based on a real die photo of the chip. Use x/z keys to zoom, and drag the mouse to pan.

The chip has five layers

• Metal: Grey

• Diffusion: Blue

• Vias: Light Blue (connect metal and diffusion)

• Transistors: Green

• Extra Structures: Yellow (No effect on the chips logic)

You can turn individual layers on/off at any time with the check boxes below the model.

You can click on nodes to highlight them and any transistors connected to them. Transistors that may affect the node's logical state become pink, while transistors controlled by the node become yellow.

Simulated Television

The simulated TV output is on the right. You can see the field being drawn as the chip runs.

• White: Area has not been drawn yet

• Grey: No signal present

• Red: Sync signal present

• Black: Score/Field present

• Blue: Left player present

• Green: Right player present

Other colors/pins will be added in a future version

Keyboard Controls

P - Step Back

N - Step Forward

Z - Zoom In

X - Zoom Out

Interacting with the chip.

Turn the game select, difficulty, and on-chip reset pins on/off using the check boxes on the right.

Change the contents of the score registers by putting new values into the smaller text-fields.

Change the paddle positions by putting the scanline number they should start at inside the larger text-fields.

Once you put the values in press "Update" (Remember, the new scores and paddles will not appear on-screen until the chip redraws that area)

Further interaction capabilities will be added in a future version.