yobbo II
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Using screen as input/output interface
When connecting stuff to a computer it can be a bit of a pain getting interface circuitry to go from the USB (or whatever) to the physical electrics.
If using a phone (if one developed an android app (or whatever)) it would be more difficult I would imagine.
Could it be possible to simply place photo transistors/diodes + associated circuitry onto areas of the screen in order to pickup output. The output
would consist of turning the areas of the screen under the photo device black or white (on/off) to give an output. Turning an area of the screen to
black or white is easy, you just put a button or text box on that area and use the background colour to give black/white. There could be many many
squares fitted on the screen.
For input you could place/stick/attach a small square of metal foil on a screen area with wire attached for physical world input (on/off anyways). You
place a software button underneath the square of foil to pickup the input.
Analog to digital and digital to analog would take a few squared but still workable. All very getto and cheap and well within the reach of hobbyist
electronic person.
It this doably. Has it been done before, anyone know. It seems kind of obvious but perhaps not a convienent or easy as I make it sound.
'Out of date' touch screen phones/tablets can be had for almost nothing nowadays.
Yob
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Fulmen
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That's an interesting idea. Don't forget that the headphone jack, it should work for both A/D and D/A.
We're not banging rocks together here. We know how to put a man back together.
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Texium
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Thread Moved 25-8-2022 at 04:31 |
Organikum
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I don't understand what this is about, tbh.
Any touchscreen is a input/output device. There are several ways to turn a not-touch device into one. Why would somebody want to poke with aluminium
foil wrapped sticks? For what purpose? Isn't this what a "stylus" is for?
I have the feeling I miss something....
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Fulmen
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This is about reusing old phones, turning the screen into a simple I/O-interface for peripheral devices. Personally I would rather use an arduino, but
I don't see anything wrong with the OP's idea.
We're not banging rocks together here. We know how to put a man back together.
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Twospoons
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Quote: Originally posted by yobbo II ![](images/xpblue/lastpost.gif) | When connecting stuff to a computer it can be a bit of a pain getting interface circuitry to go from the USB (or whatever) to the physical electrics.
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I've used Phidgets for interfacing PC to real world. Works a charm, and dead simple to drive from code (I've used C# for this).
Drivers for Windows, Linux, macOS, iOS and Android are all supported, along with half a dozen languages.
[Edited on 26-8-2022 by Twospoons]
Helicopter: "helico" -> spiral, "pter" -> with wings
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Rainwater
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If you can provide a list of hardware you wanting to use i can get you pointed to the right tutorials. Once you have a basic understanding of
programming its very simple to use an off the shelf libary
"You can't do that" - challenge accepted
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yobbo II
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Purchased input/output devices are always easier, more tidy etc.
If you needed a hugh amout of input/output devices then this may be quite cheap.
An input with a switch workes OK as shown in the picture.
I obtained some stickey backed tin foil (stuff for pipe insulaton) and a normally off switch as seen in the photo.
A small square of the foil was attached over a software button on the phone. Another large piece was placed underneath the phone (at first) and then a
few inches away from the phone.
The switch was wired between the foil stuck to the phone screen and the ground place. I switched on/off the switch using a rod of plastic.
With the ground plane underneath the phone(as pictured), the software button darkens when the switch is switched on but does not actually operate
(software 'click'). It clicks when I then put the switch to off again (open).
I suppose you could call it negative edge triggered.
With the ground place some distance from the phone (few inches) the software button clicks (operates) as soon as I turn on the switch (go from off to
on, open to closed). (Positive edge triggered I suppose).
Have to get some photodiodes or somesuch for output. Any suggestions of cheap getto optical pickup type outputs?
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