PONG REDUX

Gregg ScrantonBen Pratt

Gamespot:

Flawless! 10/10

Zero Punctuation:

The best game ever

IGN:Better than the original

1up:A groundbreaking new development

The Idea

• ATMega88PA chip controls the game logic

• DAC and ADC interface analog world with digital logic

• Oscilloscope used as the display• Paddles controlled by potentiometers

Hardware

• 8-bit DAC– SPI interface

• 10-bit ADC– Only 8-bit precision– Mux

• Two 10k potentiometers– Voltage divider

SPI wires

Y voltage X voltage

Hardware

• Tektronix 2445A analog oscilloscope– Retains old-school feel– Phosphor display offers better persistence– Ball can be a single point

• Obstacles– Buttons, knobs, and options! Oh, my!– Trace “ghosting”– Flickering

Trace artifacts

Software

• Plotting points• Ball movement– Velocity & angle variables

• Collisions– Checks against ball/paddles/boundary

• Angle of reflection is affected by angle and position of collision

• Embellishment

Software

• Main loop switches between graphics and game logic– Timing used to schedule processes

• ISR– ADC, timer overflow

• SPI

GameOver