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Topic: RGB Colour Mixer with DS touch screen (Read 7 times) previous topic - next topic

mowcius

It looks like the smallest you can get is 1.8" diagonal made for small phones etc and then you can get varying other sizes going up to about 15" but most places seem to want to sell a couple of thousand so they may be difficult to get hold of.

The DS touch screen is easy to get hold of and relatively cheap and you don't have to buy thousands :D

Just do a search for a 4 wire resistive touch screen.

Mowcius

Paul Harris

How did you go about connecting the DS touchscreen to wires you could use in the breadboard? i have one (well two actually as i assume i will mess up the connection on at least one!) and would love any tips for how you went about it. My current plan is a to cut between the wires using a modelling knife.

Does anyone know of a way to get rid of the plastic overlay thats on the wires then it would be easy to connect wires at the base of the wires.

mowcius

I just did it carefully with a sharp pair of scissors and then laid 4 wires on the connectons and soldered them up with some heatshrink round it to stop the joint flexing so much... I didn't remove any plastic or anything...

Anternatively, if you like surface mount soldering you can buy the touch screen connector from sparkfun... I presume that it works with both the DS and DS lite touch screens (it looks like it should)

Hope this helps,

Mowcius

TchnclFl

Still no video of this in action? :(  I've added one to my Wish list (2.99 free shipping on eBay, can't beat that!), but I'd love to see how yours looks while functioning :).

mowcius

#19
Nov 21, 2009, 11:29 pm Last Edit: Nov 21, 2009, 11:30 pm by mowcius Reason: 1
Oh, sorry. I dismantled it to use some of the parts as I still only have one arduino! If I remember then I will still try to a get a video done eventually. The LEDs on the picture were not evenly matched so it didn't mix very well and I have not got round to playing with the i2c commands for my blinkm maxm yet...

Mowcius

TchnclFl

Alright, well thanks for the update anyways :P!

TchnclFl

#21
Nov 21, 2009, 11:55 pm Last Edit: Nov 22, 2009, 12:13 am by Tchnclfl Reason: 1
I know it says in the code where to connect the pins from the screen, but could you please write it out?  For some reason I'm having trouble understanding it.  A picture would be useful if you have one :P.

NEVERMIND.  I believe I get it now.. :D

mowcius

Ok, cool. Just say if you need any help with anything else.

Mowcius

mowcius

Just a quick comment to anyone still looking at this. In my first posted code there are some weird numbers to get the values right for PWMing the LEDs, if you are going to do something similar then you want to 'map' the values from the touch screen to get them within the right range for the PWM.


Mowcius

TchnclFl

Quote
if you are going to do something similar then you want to 'map' the values from the touch screen to get them within the right range for the PWM.


No idea what that means (I'm still a noob :P) but alrighty! haha :D

mowcius

Quote
No idea what that means (I'm still a noob) but alrighty! haha


Well I did some rubbish like this:
Code: [Select]
analogWrite(LEDB, touchX/4 -18)
to get the values correct for the PWM (altering the brightness of the LEDs)

I should have used the map function:
http://arduino.cc/en/Reference/Map
to change the values from the touch screen into values from 0-255 for the PWM.

It is just a much better and more accurate way to do it...

Mowcius

TchnclFl

Oh so instead of using the 0-1024 produced by analogRead(), you use Map to change them to 0-255 used for PWM?

mowcius

#27
Nov 22, 2009, 06:32 pm Last Edit: Nov 22, 2009, 06:33 pm by mowcius Reason: 1
Yeah.
Well you don't get quite the full range from analog reading on the touch screen, you normally get close to it but not quite... So the map function sets it right :D

You don't get 0-1024 on analog read, you get 0-1023...

So basically if you wanted 1-1024 then you would need to map it still (or add 1!)

Mowcius

TchnclFl

Cool.  Thanks for the advice :).  Seems like that'd be simpler and faster than what you did, so why didn't you just do it that way in the first place? :P!

mowcius

I was a noob! We all were originally... If I could go back and change that post then I would. I have learnt a lot in half a year!

Mowcius

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