3D TicTacToe - Comments on Schematic

Forum 2005-2010 (read only) General Exhibition
1

Hi,
I'm quite a newbie in electronics in general (I'm a mathematician, so you can imagine my level of abstraction ;D) and after a couple of months playing with the Arduino I'm now trying to build up a full standalone project on my own.

The game is 3DTicTacToe, which is basically the classical TicTacToe (Tris) game, played on a 3x3x3 (RGB)LEDs Cube. Before starting soldering stuffs etc. (I'm also still waiting for some parts to arrive) I've started drawing the schematics of the project, but since I'm a newbie I would ask you an opinion on this schematic (I'm sure a lot of components could be added in some intelligent locations (e.g. diodes), as well as some other ones are probably unnecessary...).

To explain the project in words, the game will be built in a small wooden box, where the 3x3x3 led cube comes out (maybe under a glass sphere, recycling some empty Nutella jar :D).

  • The power can be drawn either from a USB port (only for power, no data transmission) or from a 2.1mm jack (e.g. 9V battery, wall adapter, etc.). A slider switch allows to choose the source (I suppose that with some special transistors/IC the automatic selection could be possible, but I'm not gonna complicate my life further...).
  • The user interface consists in a 3D Joystick with button (like the ones which are on the PlayStation Controller) to choose which LEDs to light up), a button to reset the game (empty the grid) and two 7-segment displays to show the actual score of the 2 players.
  • The controller part is done with an ATMEGA168 (programmed with an Arduino Duemilanove, then plugging out the chip and using it in my circuit), as well as two MAX7219 drivers for the LEDs/7Segment Displays (I'm only using two of the three colors of the RGB LEDs).

Would someone be so kind to have a look at the schematics and tell me if I'm doing some trivial errors (especially in the power supply part, but in general components could be missing everywhere: this is just what I could put down after some reasoning...).

Thank you very much! :sunglasses:


(click to enlarge)

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As far as I know, the Arduino automatically switch to USB if detected.
You are going to need a auxiliary power supply to drive more current and other stuff...

Too much load and boum.

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Hi, thanks for your reply. Actually I am not using the Arduino (I just use it to program the ATMega, but then in my project there is no Arduino anymore). I am already taking current from an external supply: do you mean that in the USB case it is not sufficient (but I suppose that with the 9V battery it is) or you were reasoning as if I would be using an Arduino? :question

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Oh yeah, I already saw a concept like this. Except it was an arduino programming another! Interesting.

I was reasoning with Arduino. From navigating 2 hours per day here (and more) I see alot of people warning others about load.

On the Arduino, each pins can run a maximum 40mA and 300 mA in total. Even then, I think these are stress value that shouldn't be experienced with or you could destroy a pin or potentionally the IC.

I don't about your Specs, just be sure everything is okay with the datasheet or ask somebody else that know a little more about microcontroller than me.

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On the Arduino, each pins can run a maximum 40mA and 300 mA in total

No 200mA in total, and even that will damage your arduino.

As to the circuit there is no decoupling on it at all, not even on the regulator output, this is vital:-
http://www.thebox.myzen.co.uk/Tutorial/De-coupling.html

By the way this section is for when you have finished something and want to show it off, not for project advice.

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Thank you for the "Decoupling" advice! :wink:

I'm sorry for having posted to the wrong section then: if some moderator could move the topic to the correct section...