64 Button Matrix Wiring

Hi

I received this shield today:

http://www.spikenzielabs.com/SpikenzieLabs/Button64Shield.html

In the 'wiring the buttons' section of the link, it shows you should connect a column pin to 8 buttons in serial then use a common diode to connect the other end to a row pin.

Before having this shield I was connecting a 10k pull down resistor to the ground connection of the button and a wire straight to the digital pin on the arduino, and the other pin was connected to 5v. I do not know how to read the components diagram.

Can you tell me how I should wire the power and ground please? It doesnt look like there is any in the photos. Are they a different sort of button maybe?? All buttons need power though right? New to electronics so basic explanations are appreciated!

Thanks in advance

I do not know how to read the components diagram.

That is fine but how can we help you if you can not follow a diagram.

That web site clearly shows you how to wire up the buttons and the diodes.

Can you tell me how I should wire the power and ground please?

You connect the 5V terminal on the board to the 5V on the Arduino and the Gnd line on the board to the Gnd on the Arduino. They are labeled so are easy to spot.

Maybe this will help explain things How to make a keyboard – the matrix | komar's techblog

Thanks for the advice.

What confused me is that as far as I can see, there is no labelling for 5v or ground on that diagram, it shows a diode and a switch per button no? I have only had experience using individual buttons that required individual power supplies. The shield sits on top of my arduino so I am presuming now that each column/row pin on the shield is supplying power for the buttons. I was not sure if this would be correct because I thought it may make fault finding harder at a later stage. I thought it was better to connect things in parallel.

Thanks

This is a matrix, what happens is that each row / column is set up as a input / voltage. Then each individual input is read to see if there is a connection between that input and the voltage.

In this way you do not need 64 inputs to read any switch but only 8 inputs and 8 outputs.

Did you read that link? Did you understand it? If not then ask about what you didn’t understand.

How you navigate with so many buttons ?

ted:
navigate with so many buttons?

What do you mean by “navigate”?

Let say you labeled each describing the function of each button on paper, make a list from 1 to 64, to know which button to press you have to find that info on the list, even if label is under the button need to do the same.

you have to find that info on the list, even if label is under the button need to do the same

No?
If you label each button you simply press it to do the function you want. While the buttons are arranged electrically in a grid, that doesn’t mean they have to be physically arranged in a grid.

On the computer end you get a pair of numbers, colour and row, you can convert that into a single key number by simply multiply and add to get a number 0 to 63, which your code then interpretes.

I have a 12 buttons phone= no problem, now I have phone with 64 buttons = lost in the jungle ?

Quite simple, don't use a 64 key matrix for a phone. It is your jungle you choose to get lost in, and if you get lost it is because you have no sense of direction.

You would label each button so why do you care what signal it returns electrically, that is the job of the software. If you are not up to the software challenge then don't do the application. Using 64 input pins for 64 push buttons is just plain stupid and you are over extending a concept. Just like babies who know about three words try and use them in all situations. You have to learn, and if you try you will find it is not hard.

ted:
How you navigate with so many buttons ?

I have 88 keys on my piano and I don't find navigating that confusing. The traditional computer keyboard has over 100 buttons and most people manage to navigate them with very few problems.

Now back to a sensible subject with any luck.

Steve

slipstick:
I have 88 keys on my piano and I don't find navigating that confusing. The traditional computer keyboard has over 100 buttons and most people manage to navigate them with very few problems.

Now back to a sensible subject with any luck.

Steve

slipstick:
I have 88 keys on my piano and I don't find navigating that confusing. The traditional computer keyboard has over 100 buttons and most people manage to navigate them with very few problems.

Now back to a sensible subject with any luck.

Steve

Smart pants # 2, and counting

Smart pants # 2, and counting

Dumb arse #3 and counting.

Sorry Mike, that was not addressed to you. slipstick knows what I mean

ted:
I have a 12 buttons phone= no problem, now I have phone with 64 buttons = lost in the jungle ?

How many keys on a PC keyboard?

Do you get lost in that too?

Edit: I've seen your code. Yes, you do.

Here is his friend #3

Great article Mike, thanks very much.