Arduino and Touchpad Tic Tac Toe

Step 2 LED matrix layout

The circuit diagram below shows how the LEDs are physically wired up (G1-G9: green LEDs, R1-R9: red LEDs).  This diagram is for single red and green LEDs, if you are using bicoloured common cathode red/green LEDs, there's only one cathode leg per red/green pair that you have to wire up.

The red and green anode lines go into the PWM pins of the Arduino (pins 3, 5, 6, 9, 10, 11 on the Duemilanove), so that we can have effects like fading later on.  The cathode lines go into pins 4, 7 and 8.

Each of the cathode and anode lines have 100 ohm resistors for protection.

Comments

[aldrome]

Hi, I really like your idea!! And i was wondering if it is really importat that The red and green anode lines go into the PWM pins of the Arduino, I mean, why do they have to be PWM?, can they be the normal pins like number 2 or 13? It's because I'm trying to mix this with another idea I have.

Thanks for everything.

[origamiwolf]

Hi aldrome,

I used PWM here because I wanted the LEDs to fade out. You can use the normal pins as well, but the LEDs will just have two brightness levels - on, or off.

-- Wolf