Trace & Character Combinations

Making progress on figuring out some of the trace combinations...

We will use the characters a, h, p, v, 3 and 5 simply because these combinations use traces that are sufficiently spaced out on the hack. Wiring could get a bit messy otherwise, it's going to be fiddly at any rate.

This chart shows what traces the wires will be connected to on our hack...

Visual Representation of the Wiring

Traces

Now that the keyboard hack is finally finished, and working properly, it is time to identify some keys for the programming side of the project.

Here is an example to explain how this works.

If we want a volume control on our Visualize product, these are the trace combinations we will use:

Numbers 1 to 12 correspond to the top 12 traces on the hack pictured (#1 starts at the top), and traces are those little black lines on the right of the hack!

• trace #12 is used, in a combination with other traces, for volume up, volume down and mute 
• trace #2 is used for volume down
• trace #4 is used for volume up
• trace #8 is used to mute the volume

How-To Mute the volume:

1. attach a wire to trace number 12
2. attach a second wire to trace number 8
3. touch the opposite ends of both wires together to mute the volume

I have illustrated it here with a push button switch...

Inside the button something the conducts electricity, like tinfoil, will touch both wires when the button is pushed down i.e. completing the circuit and muting the volume.

We will use this push-button principle to build the select button for our product.

Full Steam Ahead

The Argos keyboard works fine :)



Running a wire along the traces produces keystrokes on the screen, happy days.

Below you can see the Find and Replace box open up.  The letters continue to appear in the text box field within it.

Here we go again...

The Argos keyboard...

It only takes a few minutes when you know what you're doing.

It works! See the letters in the Word document?

RIP Hack #1

The keyboard hack overheated and died in Multimedia Group Project class today :(

The lecturer gave us a new keyboard to work on. It has a PS2 connection and is only compatible with a PC. To overcome this obstacle we used a PS/2 to USB converter device and also downloaded a driver from the Internet so the computer would recognize the keyboard via USB.

Above: Hack #2 - Keyboard from Lecturer

It wouldn't work with Apple computers. It's looking like we are going to have to buy a new one.

Keyboard Hack

The keyboard hack was a success :)

What does that mean?

The keyboard has been stripped back to its electronic components (i.e. the PCB a.k.a. keyboard hack), and the plan is to use this technology to power Visualize.

Let's try it out...

What's happening here?

• the keyboard hack is plugged into my Mac via USB
• two strands of fine copper wire are touching two separate traces on the keyboard hack
• we are working in a Word document window
• touching the two wires together is equivalent to pressing the letter c on a keyboard
• this connection produced 'c' based on the combination of traces that the opposite end of the wires are touching
• moving the wires onto different traces will give a different result, hence the '3' and 'a' on screen

Take a closer look at the keyboard hack (SK-8135):

click to enlarge photos

That strip of plastic comes out, our wires go in.