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luismoranaluismorana Posts: 3
edited 2010-01-12 03:03 in Propeller 1
Hello,
I would like to use a 15" Touch Screen LCD monitor with an application running on a Propeller chip. I understand these Touch Screens have a standard video connector and a USB connection for the touch screen grid. The USB connection works like a mouse and in a standard PC machine these monitors are plug and play with some of them needing some drivers installation.
The application I would like to develop is small but will need a touchscreen of the side mentioned above. Since the Propeller has Video output and Mouse input I think it should be possible to use a touchscreen.
Does anyone experimented with a touchscreen of this side? Any suggestion or recommendation will be appreciated.
Thanks in advance
Luis

Comments

  • MagIO2MagIO2 Posts: 2,243
    edited 2010-01-10 21:04
    Which side? Do you mean website? Do you have a link?
  • GadgetmanGadgetman Posts: 2,436
    edited 2010-01-10 21:09
    I bet he meant to write 'size'...

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  • luismoranaluismorana Posts: 3
    edited 2010-01-10 21:21
    Yes...sorry guys, I meant size...typo.
    The size of the monitor must be larger than 10" and 15" is ideal for the application I am trying to use.
    There are many "websites" that sell this type of LCD touchscreen, one is Tigerdirect but there are many others.
    Thanks
    Luis.
  • Mike GreenMike Green Posts: 23,101
    edited 2010-01-10 21:39
    The Propeller mouse routines expect a PS/2 mouse while the devices you describe provide a USB mouse. These are not the same. While some people have been experimenting with a USB client driver for the Propeller, what you would need is a USB host driver which is very very different. You should be able to use a Parallax Memory Stick Datalogger or one of the Vinculum equivalents to provide a USB host that can talk to a mouse. There's no ready-to-go I/O driver that I know of that would do this for you.
  • Phil Pilgrim (PhiPi)Phil Pilgrim (PhiPi) Posts: 23,514
    edited 2010-01-10 22:56
    There are USB->PS2 plug-in adapters for USB mice that work quite well with the Prop. It used to be that every USB mouse came with one, but that's probably no longer the case. I've used one between a wireless USB mouse dongle and the Propeller Demo board without any problems. Something like that might also work for your monitor.

    -Phil
  • Mike GreenMike Green Posts: 23,101
    edited 2010-01-10 23:01
    The USB->PS/2 adapters are simply plug adapters. They have no circuitry in them. Some older mice had firmware that would detect whether they were connected to a PS/2 port or USB port and adjust themselves accordingly. Current mice and keyboards, unless they're spec'd that way cannot do this. Don't waste your money unless you know the mouse port can work this way.
  • CassLanCassLan Posts: 586
    edited 2010-01-10 23:02
    Many Touchscreens from Elo still come with Serial communication.

    I have found them very helpfull, and willing to send a detailed description of the Data Packet sent from the screen. When I get back to the office I will put it up.

    Rick

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  • TubularTubular Posts: 4,726
    edited 2010-01-10 23:10
    Luis,

    You need an older style touch monitor which has serial output. These are commonly used with Point of Sale PC's at restaurants etc. I think they are still available, perhaps from ELO or 3M

    I have experience interfacing Gunze (Japan) 15" touch panels via serial... I'm guessing you don't want to build your own monitors/panel PCs from scratch, though?

    Gunze have small touch panel converter modules which covert the 4/5/8 wire touch signals to RS232 or USB. You could always hack your preferred monitor to make it output serial instead of USB
  • Phil Pilgrim (PhiPi)Phil Pilgrim (PhiPi) Posts: 23,514
    edited 2010-01-10 23:13
    Mike,

    Ah, so! I've always wondered what was inside one of those little adapters to deal with the "USB conversion". You've just saved me the trouble of cannibalizing one to find ... nothing! smile.gif

    -Phil
  • BradCBradC Posts: 2,601
    edited 2010-01-11 00:42
    Both the 3M (MicroTouch) and ELO (ELOTouch) Protocols are very well documented and extremely easy to use. I'd highly recommend the ELOTouch screens that use SAW location rather than any of the resistive or capacitive matrix screens. I've got some early ELOTouch screens here that have a few years of 24/7 use on the clock and are on their second CRT. The screen sees a couple of hundred touches a day and has done since '91. The beauty of the SAW screens is they just don't drift. You set them once and they are pretty much calibrated for life.

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  • luismoranaluismorana Posts: 3
    edited 2010-01-12 01:11
    All,
    Thank you very much for all the answers and suggestions. The serial port connection might be the best way to go.
    As a matter of fact, I saw those USB to PS/2 adapters and thought to connect the Touchscreen into this USB-PS/2 and then into the Prop.
    Too simple!!!.
    I will experiment a bit and see what I can come up with. I will publish my findings in this forum so someone else might use it as well.
    Thank you again.
    Luis.
  • TubularTubular Posts: 4,726
    edited 2010-01-12 01:35
    luismorana said...
    All,
    As a matter of fact, I saw those USB to PS/2 adapters and thought to connect the Touchscreen into this USB-PS/2 and then into the Prop.
    Too simple!!!.

    Luis, you can certainly try that. I fear it may indeed be "too simple" and won't work straight up.

    Using a "dumb" USB to PS2 adapter relies on the USB chip inside the touch screen supporting "dual mode" - USB and PS2. I'm talking about chips like Cypress Encore series (or others from TI etc) which are often used in keyboards and mice. Some touch screens have a specific driver to interpret their proprietry data stream - in which case it wouldn't would with the Prop's PS2 Mouse Object without modification.

    Do you already have a touchscreen and if so, what model? Perhaps we can shed some more light on this
  • BradCBradC Posts: 2,601
    edited 2010-01-12 03:03
    I'm not sure you will get a PS/2 to give you relevant information for a touch screen anyway. A touch screen requires absolute coordinates. A PS/2 mouse protocol is geared for relative coordinates. In addition, without raw data to work with, you have no way of applying calibration offsets to make sure you are actually touching where you think you are. Generally touch screens that use a USB interface don't emulate a HID device, as there is no way of applying calibration data to that anyway, they use their own driver.

    Years ago in one of my windows applications, I took a serial touch screen in, did my own calibration and processing on it and simply emitted absolute mouse move and mouse button events directly into the windows event queue. It worked a treat and meant you could plug in any number of touch screens to use this application with out any driver installation required on the PC. As a bonus, if the application was minimised the touch screen continued to work just like a mouse.

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