How Commodore changed… PONG

Those of us that have experienced and seen the 70s, have seen the birth of the videogame industry, thanks to Ralph Baer.
Ralph worked as a TV engineer at Loral, where he dreamt up the concept of “playing games on a TV” as early as 1951.  His boss did not really see any viable future for this idea, so it wasn’t until 1966, when he built the first prototypes, that the concept of video games became a reality.

The last of his prototypes, built in 1968 (also known as “Brown Box”) played ball & paddle games, target shooting games, and more.  The PONG games were born!
After Magnavox licensed these and released the first ever video game system in May 1972: the “Odyssey”, Atari released the first PONG arcade game in November 1972.
The whole PONG experience was quickly adapted (or copied if you will) by numerous other companies like Sears, Coleco and Commodore.

Commodore’s contribution might have been obscured in history as “just one of the many PONG clones”, but it has to be said that the two systems it released, the 2000K and 3000H (also referred to as the TV Game series) were quite different as they were the first programmed systems to play PONG.

   
The 2 models of the TV Game series: the 2000K and the 3000H

Let me explain this small revolution by examining the different systems in more detail.
In essence, all the PONG clones and variants came in 3 flavors: Analog systems, digital systems and “PONG in a chip” systems.

The analog PONG systems (like the Magnavox Odyssey) basically stored all the game parameters (like ball and paddle positions, game speed, etc.) as variable voltages in capacitors.  This made them rather unstable and delivered a low quality video signal.  Touching the pins of the capacitors would alter the voltage slightly, giving unexpected results in the logic.

The digital PONG systems, unlike their analog counterparts could not be hindered by slightly varying voltages as the game parameters were encoded in binary format, represented by a 5-volt and a 0-volt potential.  If these signals got altered, it had basically no effect because any voltage around 5 volts would always be considered as a logical 1 and any voltage around 0 volt would also be considered as a logical 0.

Then there were the “PONG in a chip” consoles.  They basically had the entire game logic in one single chip.  General Instruments made the most widely used range, called the AY-3-8xxx.  These chips were quite cheap (less than $10) and required very little other components.  If you were a bit of a hobbyist, you could purchase the AY chip and the schematics and build your own PONG console.


That’s me, with the 2 consoles and some of my Commodores in the back

What made the Commodore machines stand out from the crowd, was the fact that they used a separate microprocessor (in this case the MOS 7600/7601), which read game instructions from a special ROM.
This microcontroller hence was customizable in theory, as it could read software from a separate storage medium (in this case ROM) and play different games, without changing the actual core logic of the chip (which was of course something that was impossible with the “PONG on a chip” consoles).
I do have to stress the “theory” bit there, as graphics and sound were generated directly by the 7601 and were hence hardwired into the chip’s logic.
It meant that special variants had to be created if a special display was required for an arbitrary application.

Nonetheless, the 7601 in the Commodore TV Game series, while being programmable in a crude sense, was a taste of things to come and a first of its kind.

On the outside, both machines are quite different.  The 2000K uses the classic PONG paddles, whereas the 3000H has sliders.  One of the paddles on the 3000H is located on the console itself.  A turn-dial on the 2000K, a slider on the 3000H selects one of the four games: Tennis, Target (with an optional light gun), Football and Squash.
On the inside however, things are basically the same, with the core being the 7600/7601 chip.

   
The 2000K and 3000H internal.  The former is quite difficult to open, as the turn-dial “locks” the board in place

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5 Responses to How Commodore changed… PONG

  1. Hi,
    I actually had a 3000 console when I was about 8 (must have been in 1980)
    Anyway – I played it loads (apart from the skeet shoot as I didn’t have the light gun) but after about 45 mins it used to overheat and the ‘ball’ would bounce around the borders of the screen!

    I would have to let it cool down before playing again.

    Happy days…

  2. At our anual Pong to Playstation event in the netherlands I actually was able to play one of them… It was funny to see that the score was only displayed when there were no paddles on the screen due to memory limitations… Great fun!

  3. So… I have a 2000K, which could still be working. But I don’t have the power adapter. It was a DC 708. I believe that it used a center positive plug and was 9 volts. Please could someone confirm this and also tell me what sort of plug to use? The various adapters I have don’t quite fit…

    Thanks, Nick.

  4. I have a CBM 3000H, that still works, but the second controller is wonky, and judders, a squirt of WD40 settles it, I never saw a light gun for this? It’s got a repair ticket on it for I think 1978/9, but I thought they brought this out in 79? Never understood why it has German/English writing on the controls?

    Nick – Generally the adaptors used are 9v inside, the outside being ground. You can get the adaptors from Argos with multiplugs, for under a tenner?

    I read a rumour that these machines fetch vast money when sold? But see no evidence.

  5. Robby "The C= guy"

    They do raise quite a few $$, but nowhere near anything a Max Machine or a C65 would get :)
    The German would be because the units we’re also sold in Europe (just like about any other PONG clone out there) and in some countries, selling products in the native language is a must.

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