Is there a way to simplify this circuit ? (2 players reaction tester game) - Page 1
Forum section: electronics / beginners

author: tigrou
author_rank: Regular Contributor
timestamp: December 30, 2024, 10:27:58 pm
content: Thiscircuitis a 2 players reaction game.The goal is to be the first to press a button after some random event (eg: buzz sound). This is not from me but from Kosmos 2000 electronic kit.I was wondering if it was possible to do a 3 players (or more) version and ended withthis.While it works, it use 6 transistors and the 4 players version is going to use 12 transistors !Is there a way to simplify it ? (eg: use less components)

author: amyk
author_rank: Super Contributor
timestamp: December 31, 2024, 02:33:27 am
content: Quote from: tigrou on December 30, 2024, 10:27:58 pmUse a microcontroller

author: coromonadalix
author_rank: Super Contributor
timestamp: December 31, 2024, 03:21:12 am
content: you have many possibilities, 555 based, transistor based. mcu list goes on and on etc ...this one is simple in a way :https://www.circuits-diy.com/school-college-quiz-buzzer-circuit-electronics-projects/you can add many stages as you want ... but simplicity mmmyour link does offer some simplicity too, you add more stages ...

author: KrudyZ
author_rank: Frequent Contributor
timestamp: December 31, 2024, 03:37:02 am
content: Quote from: tigrou on December 30, 2024, 10:27:58 pmThe problem with this circuit is that you also "win" by hitting the button before the event happens.Also, why are the two base resistors of different value???

author: tigrou
author_rank: Regular Contributor
timestamp: December 31, 2024, 08:28:38 am
content: Quote from: amyk on December 31, 2024, 02:33:27 amSure, but where is the fun ?Quote from: KrudyZ on December 31, 2024, 03:37:02 amThere is other flaws as well, like pressing all 3 buttons at once, then releasing the winning one (and still holding the 2 other buttons) might end up lighting 2 LEDs.Maybe this only happen in the simulation (which is close to perfect unlike real world).Quote from: KrudyZ on December 31, 2024, 03:37:02 amProbably because the kit only provide a limited set ofresistors, so two different values had to be used.The circuit ishere.Quote from: coromonadalix on December 31, 2024, 03:21:12 amI like it. Thanks. I also start thinking about using a bunch of logic gates (usually multiple ones are packed in a single IC).

author: jpanhalt
author_rank: Super Contributor
timestamp: December 31, 2024, 09:36:59 am
content: I think you need a latch. In Jeopardy, some (most) contestants hit the button and release. That would allow a very close second place light to stay on if its button was held.A switch debouncer circuit may work, but I second the micro as the simplest solution. Plus, the micro will give you the option of showing reaction time in milliseconds.

author: tigrou
author_rank: Regular Contributor
timestamp: December 31, 2024, 11:24:23 am
content: Quote from: jpanhalt on December 31, 2024, 09:36:59 amSomething likethat.As a bonus :- Reset pin is used to reset the whole thing- D pin is used to prevent players pressing button before they are allowed to do so (input is ignored). Holding button before that signal will have no effect.

author: jpanhalt
author_rank: Super Contributor
timestamp: December 31, 2024, 11:34:54 am
content: That does seem to work and latches. But, it's a lot of parts and still doesn't give the time. Being the fastest of three is important, but an actual time that you can wear on an arm band is more impressive for bragging rights.

author: tigrou
author_rank: Regular Contributor
timestamp: January 02, 2025, 03:14:17 pm
content: Here is555version, based oncoromonadalixanswer.Improvedversionof the OP circuit, using only transistors / resistors / diodesThere is probably lot of things to be improved (suggestions are welcome) but it's much better as it can scale easily.

author: amyk
author_rank: Super Contributor
timestamp: January 03, 2025, 08:52:57 am
content: If you don't want to use an MCU, how about a small CPLD?

author: tigrou
author_rank: Regular Contributor
timestamp: January 03, 2025, 02:38:40 pm
content: Challenge acceptedCode:module quizz (input wire reset,input wire enabled,input wire player1,input wire player2,input wire player3,output reg led1,output reg led2,output reg led3);wire allowed = !(led1 | led2 | led3) && enabled;always @(posedge player1 or posedge reset) beginif (reset) beginled1 = 1'b0;end else beginled1 = allowed;endendalways @(posedge player2 or posedge reset) beginif (reset) beginled2 = 1'b0;end else beginled2 = allowed;endendalways @(posedge player3 or posedge reset) beginif (reset) beginled3 = 1'b0;end else beginled3 = allowed;endendendmoduleCan be testedhereThe synthetized layout is as simple as it can be :

author: jimmc
author_rank: Frequent Contributor
timestamp: January 03, 2025, 03:39:37 pm
content: How about this, can be expanded as required

author: DavidAlfa
author_rank: Super Contributor
timestamp: January 03, 2025, 04:22:27 pm
content: Here you have, unlimited players, zero parts, the one that touches enables a very bright indicator.

author: tigrou
author_rank: Regular Contributor
timestamp: January 03, 2025, 05:22:28 pm
content: Quote from: jimmc on January 03, 2025, 03:39:37 pmWorks like acharm.Quote from: DavidAlfa on January 03, 2025, 04:22:27 pm