Author Topic: Needs pen advice for class demo  (Read 7238 times)

Offline NickStergiou

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on: April 13, 2008, 08:04:50 PM
Forgive me for not going through the topics and looking for my answer.

The reason for this (besides that I'm lazy) is that I am doing a study on the wiimote hacking culture and wiimote hacking in general. It is also important to me to document how much everyone helps out on these boards (for my class website, you can go to http://www.mushon.com/spr08/nmrs/. So far I've managed to use the wiimote as a mouse and proud as a little girl.

I am hoping to do a demonstration on a whiteboard. Only trouble I am having is how to make the pen. Well, I bought a few of those 25 degree 25 mW Vishay Semiconductors Infrared Emitting diodes... I am aware that I need to use some sort of battery (a 9V?) but not certain on what else I might need and how to connect it.

I'm also having a bit of trouble connecting my laptop to my school projector but that may be a little out of bounds here...

Any help would be appreciated.

Thanks!

-Nick



Offline taitrt

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Reply #1 on: April 13, 2008, 09:23:40 PM
You need a 1.5v battery (all normal batteries are 1.5v, that includes AA, AAA, C, and D).

1. Connect a wire to the - end of the battery and attach it to one side of the LED.

2. Connect a wire to the + end of the battery and attach it to one end of a momentary push button switch, attach the other end of the switch to the other side of the LED.

3.  ??????

4. Profit.

P.S. If you turn on your cell phone camera you'll be able to see the IR light from the LED when you push the switch.  If you don't see the LED turn on just swap the sides of LED that you connected the wires to.
 
« Last Edit: April 13, 2008, 09:25:29 PM by taitrt »



Offline UndCon

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Reply #2 on: April 14, 2008, 02:16:25 AM
The LED has to be connected the right way... There are 2 strands on the LED - 1 short and 1 long...
There is also a flat side indicating the negative(-) side

scroll down on this side to view a describing pic on the LED

http://en.wikipedia.org/wiki/LED

here is my pen - dead simple...

http://undcon.com/mods/irpen



Offline NickStergiou

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Reply #3 on: April 15, 2008, 12:02:48 AM
Hey guys thanks a bunch. I was able to make the pen, and even had fun breaking little light keychains I had make more pens. However... I had trouble calibrating the wiimote with the software Johnny Lee made. I'm trying to use my pen to write on my laptop for now... I made a video for you guys to hopefully better explain:

[youtube]http://www.youtube.com/watch?v=8lZjbe5lK7g[/youtube]



Offline UndCon

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Reply #4 on: April 15, 2008, 04:25:09 AM
Ahh - instructables - well done, happy "wiimote-ing"



Offline atomriot

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Reply #5 on: April 15, 2008, 10:40:22 AM
Nick, a couple things:

the switch needs to turn the LED on, not off. im not familiar with that switch and how it works but it seems it may be the wrong one.

you can check in your camera to make sure the LED is only on when you press the button.

as for the video, perhaps just recording what you have as a problem and not your dogs, heh.

the reason the calibration goes haywire is because you are having the led always on so it is constantly getting a signal. if you correct your switch issue, that will alleviate the problem.

what is the model of that switch you used again? try and put some of the pertinent info in the post, not just on youtube.


Details, details. Things to do. Things to get done. Don't bother me with details, just tell me when they're done.
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James Lionel Price



Offline UndCon

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Reply #6 on: April 15, 2008, 11:50:44 AM
thats right - the switch should turn the led on...not off



Offline NickStergiou

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Reply #7 on: April 15, 2008, 12:45:22 PM
I believe it's the model 275-1547... not the 1571 which I was looking for because they didn't have one available at the time. I'm not sure why it's doing this. Perhaps if I switch the positive and negative wire in the openings in the switch?

Oh and my pets are oscar nominated. SO LAY OFF! ;-)

Another question I had is do I have to have the wiimote at a certain angle on the screen (I plan on trying with a projection overhead this afternoon so I'm keeping this in mind). I think I remember Lee saying the whitemote had to have a 45 degree angle on the board.

Thanks again for all your help, I really really appreciate it.



Offline atomriot

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Reply #8 on: April 15, 2008, 01:23:09 PM
that switch should be fine. the idea is that it creates a current no matter which way it goes. are you sure that your not touching the end of the led to the other terminal or your solder isnt bridged or something?

as far as angles, thats what the calibration is for. when you calibrate it lets the software know what orientation you are using the wiimote in so angles only begin to matter when you are at too high of an angle from the area you are using the wiimote in.

Details, details. Things to do. Things to get done. Don't bother me with details, just tell me when they're done.
--
James Lionel Price



Offline UndCon

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Reply #9 on: April 15, 2008, 03:40:10 PM
In the calibration its much like finetuning...

The camera has a 45 degree field of view so you have to move it far away enough to cover your workspace - be it the kitchen door like i used in this pic
http://www.undcon.com/mods/irpen/img_9663.jpg

or a tablet area like this
http://www.undcon.com/mods/irpen/img_9658.jpg

My switch has 3 pins...
if I connect wires to pin 1&2 the power is always on and the button breaks the loop
if I connect wires to pin 2&3 the power is off and turns on when button is pressed (closes the loop)