Looking at the 1974 arcade game Speed Race, I notice that the cabinet includes ancillary LEDs to show the scores.


That reminds me of the Wozniak version of Breakout, which likewise used an ancillary LED. Atari wanted the score shown on the CRT instead, and they couldn't figure out how the design worked, so they scrapped it and redesigned from scratch, though the redesigned version did not match Woz's economy of components.

(This was not Woz's fault; it was the fault of the arrangement where, instead of the company talking directly to him, Jobs was the middle man in a game of telephone. It's an example of why design by 'toss the requirements over the wall, get a completed design tossed back' doesn't work. There will always be something you forget to spell out in the requirements, always something that needs to be adjusted.)

And I've been wondering, if Breakout ended up showing the score on the CRT, why didn't Speed Race? It's not because the technology of 1974 wasn't up to it. Pong showed the score on the CRT in 1972.

Conjecture: it took significant effort to design a compact circuit to show the score on the CRT. Perhaps the ancillary LEDs added manufacturing costs to Speed Race, but made the design easier, thereby achieving faster time-to-market? That would require the LEDs to cost more than the saved logic gates, but if that's not the case, then I would expect at least one of Pong and Breakout to use LEDs.

  • 7
    Is there some "attractor" benefit? The CRT is angled and thus not immediately visible to passers-by. Showing the score to potential competitors may encourage more quarters to be deposited.
    – dave
    Commented Dec 30, 2021 at 23:52
  • 1
    those "ancillary LEDs" are called 7-segmend LED "display" ... LCD might be just wrong translation/transcription (you know engineer say display and manager/seller wrote LCD) not sure when LCD's emerged but I definately see those after 1984 in hand held games, digital watches and diars... but I am "sure" they where around much longer before that
    – Spektre
    Commented Jan 2, 2022 at 6:29

1 Answer 1


It may be impossible to give a simple answer, as a design is influenced by many parameters. Complexity (and thus price) might being one

A notable difference between these three games are the number of digits displayed, which goes direct into circuit complexity.

  • Pong has two 1.5 digit counters (0..15) (*1)
  • Speed Race has two 3 digit counters
  • Breakout has
    • one 1 digit player counter (1..2)
    • two alternative displayed 1 digit ball counter (1..5)
    • two simultaneous 3 digit score counters

Pong needs 14 (!) of its 66 TTL, or more than a fifth of it's logic, just to display the two 1.5 digit score counters.

In contrast, displaying the two 3 digit counters of Speed Race on LED is rather straight forward done a counter with parallel output and a 7 segment decoder, like 7490 and 7466. If not using a 74143, integrating both into a single chip. Reducing the more complex displays to less than half the number of TTL. Doing the same on screen might have been way more complex than what Pong needed.

For Breakout complexity will multiply even further. Keep in mind, these counters aren't simply converted by a character generator and turned into pixels by serialisation, but generated by timing circuits and flipping between 4 different pattern selected by logic combination from counters.

Long story short: It's about cost. Manufacturing as well as design cost.

One LED unit plus 1 TTL per digit is way less expensive than doing the same on screen. Neding, in comparison, next to no design effort.

By 1976 TTL prices have not only dropped, but competition was strengthening, so Atari had to offer a better, more sleek design - while at the same time being sure to be able to score a good price for each unit, equalizing the higher design and production cost.

*1 - Winning score could be selected by a switch as 11 (like ping pong rules tell) or 15. It was held in a 'shortened' 5 bit BCD form with the lower digit stored in a 7490 BCD counter plus a 74107 flip-flop for the tens.

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