From today’s perspective, it seems strange that an arcade machine didn’t even have a CPU at its heart. However, this is true for Pong and several other early gaming machines/systems.
Rather than a CPU and software, Alcorn built the game experience entirely from hard-wired transistor-transistor logic (TTL) circuits. Dedicated circuits were created for each aspect of the arcade experience, such as video signal generation, paddle movement, collision detection, and scoring – all wired together to work in harmony. A simple oscillator generated the blippy audio feedback, which became iconic in its own right.
I don't know anything about this stuff and I'm absolutely not a hardware guy. I googled "TTL eli5 transistor-transistor logic" but the results were utter crap. I have some questions.
Could I get a eli5 on what a TTL is and why it was used back then?
Why was TTL used? My guess is lower cost and it was simpler. How accurate is that?
Is TTL still used?
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PorkrollPosadist [he/him, they/them] - 1w
In addition to a handful of other uses, transistors are the fundamental building block of digital logic. They allow a circuit to perform logical operations like AND / OR / XOR / NOT. Even today, the most state-of-the-art computers are designed by composing these primitive functions (on the scale of billions of transistors in a modern CPU). In 1972, microprocessors were a very new technology, but all they did was essentially pack thousands of transistors into an integrated circuit which provided a collection of mechanisms for executing instructions and performing basic arithmetic. Intel's first CPU, the 4004, introduced a year earlier in 1971, packaged 2300 transistors in a single integrated circuit.
For a lot of electronics and industrial control mechanisms, a solution could be implemented with a much more (schematically) simple circuit. There was no need for things like addressable memory, or reading and executing arbitrary instructions if your goal was e.g. to turn on a motor when a signal is coming from one of two sensors but NOT from a third. Such a circuit could be built from a handful of standard components, rather than a (at the time) state-of-the-art piece of silicon.
Tychoxii in technology
Pong debuted [a few days ago] in 1972 — Atari's pioneering CPU-less video arcade game’s creation was the result of an engineer training exercise
https://www.tomshardware.com/video-games/retro-gaming/pong-debuted-on-this-day-in-1972-ataris-pioneering-cpu-less-video-arcade-games-creation-was-the-result-of-an-engineer-training-exerciseI don't know anything about this stuff and I'm absolutely not a hardware guy. I googled "TTL eli5 transistor-transistor logic" but the results were utter crap. I have some questions.
In addition to a handful of other uses, transistors are the fundamental building block of digital logic. They allow a circuit to perform logical operations like AND / OR / XOR / NOT. Even today, the most state-of-the-art computers are designed by composing these primitive functions (on the scale of billions of transistors in a modern CPU). In 1972, microprocessors were a very new technology, but all they did was essentially pack thousands of transistors into an integrated circuit which provided a collection of mechanisms for executing instructions and performing basic arithmetic. Intel's first CPU, the 4004, introduced a year earlier in 1971, packaged 2300 transistors in a single integrated circuit.
For a lot of electronics and industrial control mechanisms, a solution could be implemented with a much more (schematically) simple circuit. There was no need for things like addressable memory, or reading and executing arbitrary instructions if your goal was e.g. to turn on a motor when a signal is coming from one of two sensors but NOT from a third. Such a circuit could be built from a handful of standard components, rather than a (at the time) state-of-the-art piece of silicon.