Oscilloscope pong for 1 or 2 players. - Page 1
Forum section: electronics / projects

author: GK
author_rank: Super Contributor
timestamp: March 12, 2017, 05:07:11 pm
content: EDIT: (4/4/17). For a complete set of schematics and equiv. diagrams collated into a single PDF document click:http://www.glensstuff.com/pong/Oscilloscope_Pong.pdf--------------------This weekend I started soldering discrete components together like a man possessed and this is what came of it.There are four switchable modes of play:1) Machine against machine2) Player 1 against machine3) Player 2 against machine3) Player 1 against player 2Player one controls the paddle on the left and player 2 the paddle in the right. The hand controllers are just zippy boxes each with a pot and knob, though the player 1 controller sports a "serve ball" momentary push-button. A match/game starts on the pressing of this button.In the attached video (mode 2) I am playing against the machine, which is controlling the paddle on the right. The velocity of the ball begins at a slow and easy rate but in order to ensure a match cannot last forever, from the start of play the ball velocity linearly ramps up. It will continue for as long as the player(s) can keep up with it.If either player misses the ball the match ends with a 150 Hz bzzztttt and the ball is automatically returned to the center of the court where it remains stationary until player one presses the "serve ball" button to commence a new match.The sound in the youtube video is a bit quiet and you have to crank the volume up a bit to hear all of the sound effects.

author: Unknown
author_rank: Unknown
timestamp: March 12, 2017, 05:17:48 pm
content: Hah, they have something exactly like that at theLiving Computer Museum(Seattle, WA).Very nice!

author: GK
author_rank: Super Contributor
timestamp: March 12, 2017, 05:19:25 pm
content: The circuity is 100% discrete and built entirely "dead bug". With the exception of a 2N2219A/2N2905A complementary pair for driving the speaker, it's all BC550C and BC560C, a bunch of 2N5484 FETs for analogue multiplexing, lots of 1N4148 and a few zeners. There is close to 200 transistors, I think; I haven't counted them yet.I'm currently drawing up all of the schematic diagrams for presentation and collating them into a single multiple-page PDF document. I'm only currently half way through; some teasers attached. It's getting onto 4am now' I'm going to bed.

author: BrianHG
author_rank: Super Contributor
timestamp: March 12, 2017, 05:21:34 pm
content: I see you took my recommendation from you telefunken bouncing ball post a month or 2 back.Great job. I like the fact that you ball is round and you have a center court net while other oscilloscope pong games are nothing more than a dot for a ball with 2 paddles.Wow, that would drive me nuts trying to wire today. In my high-school years, if I would have a scope at the time instead of an Atari 800, I would have attempted something like that for the challenge.

author: Howardlong
author_rank: Super Contributor
timestamp: March 12, 2017, 05:21:53 pm
content: Maximum respect!

author: sentry7
author_rank: Regular Contributor
timestamp: March 12, 2017, 05:28:57 pm
content: Cleanest point-to-point execution for a scope pong game I think I will see for a while....it's definitely a 10. Kudos to you. William Higginbotham would have been proud. The video game industry in all of it's awesomeness started with this circuit.

author: Rolo
author_rank: Regular Contributor
timestamp: March 12, 2017, 05:38:26 pm
content: That is a piece of art. If you're done playing with it you can hang it on the wall. Well done !

author: BrianHG
author_rank: Super Contributor
timestamp: March 12, 2017, 05:42:47 pm
content: I have one minor addition for the analog computer player which might not be to difficult to incorporate. Instead of making the paddle track instantly the balls vertical location, add an inductor/cap/adjustable resistor (the inductor is to give the computer player a life-like wave motion instead of just speed limitation) delay to fudge up the positioning of it's response giving the player a chance to win when the ball gets really fast. Having a difficulty skill setting for the analog computer by setting how fast and accurate it's paddle responds...Once again,an amazing work.

author: sentry7
author_rank: Regular Contributor
timestamp: March 12, 2017, 05:55:02 pm
content: I've studied for years on how back in the late 60s - early 70s, getting this circuit from the scope to TV was the Mt. Everest of the budding video game industry.Allan Alcorn who was a young upstart at Atari and designed the original PONG in '72 talked about how Nolan Bushnell (then CEO) lied to him and told him that they had a contract with General Electric. He tricked him into getting a working prototype in less than a week! After that, Bushnell decided he wanted sound too!

author: GK
author_rank: Super Contributor
timestamp: March 12, 2017, 06:20:07 pm
content: Quote from: BrianHG on March 12, 2017, 05:21:34 pmKinda. I was reading up on the original arcade video game (https://en.wikipedia.org/wiki/Pong) and found the schematics. That was all done in TTL. My first idea was to recreate the original TTL (logically) in discrete, but that would be more than I can spare the time for right now. So, drawing from my previous bouncing ball stuff I decided to do it analogue (well mostly) for display on a 'scope rather than a TV. The circuity here is entirely my own, BTW.QuoteThanks. My initial plan didn't include the court divider, but that was actually added as a circuit simplification when I finalised the display control logic. Instead of having a counter that goes 0-1-2-0-1-2, decoded to reset on 3, to display paddle, paddle, ball, I added a fourth object (the court divider) so that my counter could be simplified to a 2-bit ripple.Now I really have to get to bed, the sun is going to start rising soon!

author: DaJMasta
author_rank: Super Contributor
timestamp: March 12, 2017, 07:17:35 pm
content: Very cool, I can't for the life of me figure out why you'd want to do that dead bug style, though. All those flying leads just make me think I'd drop a screwdriver on it or something and just be out of luck.Anyways, I know polyester caps in an integrator is good form and all, but is that actually required for this application? Is there enough fluctuation in other cap technologies for visible issues?Still, very nice execution and great schematics - I think more than a few other people would want to build up this design.

author: 2N3055
author_rank: Super Contributor
timestamp: March 12, 2017, 10:00:56 pm
content: Respect!!!

author: ChristofferB
author_rank: Frequent Contributor
timestamp: March 13, 2017, 12:58:28 am
content: Amazing manhattan-style craftsmanship! You must have the patience of a saint!

author: tautech
author_rank: Super Contributor
timestamp: March 13, 2017, 01:07:38 am
content: Thanks for sharing another of your neat projects with us GK.

author: mmagin
author_rank: Frequent Contributor
timestamp: March 13, 2017, 03:02:17 am
content: You built this in a single weekend? I wish I was so insanely productive. Wow.

author: GK
author_rank: Super Contributor
timestamp: March 13, 2017, 03:43:08 am
content: Yes, but I did all of the design work (drafted mostly in LTspice) the past week. Didn't get much else done this weekend though!Slowly working through the re-drawn schematics........

author: GK
author_rank: Super Contributor
timestamp: March 13, 2017, 04:12:47 am
content: EDIT: Just corrected a small omission on the Ball Horizontal Movement circuit. Hmm............ think I'll put my pen and paper down for a bit now, log off and go off and eat something......

author: james_s
author_rank: Super Contributor
timestamp: March 13, 2017, 04:56:09 am
content: Holy crap! That's amazing!

author: boffin
author_rank: Unknown
timestamp: March 13, 2017, 06:14:58 am
content: anyone else have the sudden urge to bow multiple times while chanting "we're not worthy" ?

author: Berni
author_rank: Super Contributor
timestamp: March 13, 2017, 06:28:30 am
content: Now that is a amazing project right there!I know this can be done with one MCU and some resistors but it would not be anywhere near as cool. There is not even any opamps in there!

author: JPortici
author_rank: Super Contributor
timestamp: March 13, 2017, 06:51:34 am
content: Sir, you are insane.*takes a bow*

author: MK14
author_rank: Super Contributor
timestamp: March 13, 2017, 07:25:11 am
content: It's amazing what can be achieved, with a modest pile of discrete transistors, some passives and a blank (copper) piece of PCB. I'm amazed (as well as at the whole project/game) at the quality/accuracy of the sound effects, the quality of the nicely sized round ball and the multi-mode capabilities, including a man vs analogue computer mode.The picture quality is so smooth and stable, despite the fact it is analogue and made in a way which would worry me (short circuits etc).If I was told about such a project, I would not have expected it to be analogue, have no integrated circuits, be made without a PCB, be so (relatively) neatly constructed or work so well and with such quality in measurable ways.

author: GK
author_rank: Super Contributor
timestamp: March 13, 2017, 07:37:06 am
content: Quote from: Berni on March 13, 2017, 06:28:30 amI count 9 op-amps!