Hi
I would like to know which LCD touchpanel could be use with the
beagleboard
Thanks
Out of the box, none. In order to use a particular LCD or Touchpanel an adapter board will need to be created to convert the required logic levels of the LCD panel you want to use. All of the signals are 1.8V as described in the System Reference Manual. In addition, you will have to provide the required touchscreen controller and backlight driver circuitry.
Gerald
Hello Gerald,
A small LCD would be the perfect companion for the Beagle - do you have
any plans to make an adapter board and offer it via DigiKey?
Marcus
There is on one in the works, but it will not be through DigiKey but another source. It is a board with the PSP LCD on it.
Gerald
Hi.
I would like to refine my question.
I connected my 15” inch LCD screen to the beagleboard via a DVI cable and would like to have a usb based touch screen panel (4-wire resistive) connected to the beagleboard. Did any one did such a thing?
Thanks.
Yes. DigiKey has one. http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail&name=653-1003-ND
You can find other sizes here as well http://dkc1.digikey.com/us/mkt/beagleboard.html
Gerald
Will it be usable with other LCDs with similar interface specs but
different resolution?
Marcus
A touchpanel has nothing to do with the LCD resolution. It just needs to fit the panel.
Gerald
Hi
I need to use a 4-resistive touch panel and not other technology like
capacitive/infrared etc.
Is it possible to use any touch panel (resistive) with the beagleboard?
Shall one customize the touchpanel driver for the beagleboard?
Thanks
The interface to a touchpanel is a touchpanel controller. Depending on what interface that partuclar controller uses, will determine what is required of that driver and whether or not one already exists. The TPS2046 is a common controller and there are already drivers available for that partuclar controller i fthat i sone that you have selected.
Gerald
The interface to a touchpanel is a touchpanel controller. Depending on what interface that partuclar controller uses, will determine what is required of that driver and whether or not one already exists. The TPS2046 is a common controller and there are already drivers available for that partuclar controller i fthat i sone that you have selected.
Digikey has a TSC2046EVM, which I connected to the BeagleBoard via level translators. I used a touchscreen from Sparkfun
http://www.sparkfun.com/commerce/product_info.php?products_id=8448
I used the 1.8v from the BeagleBoard and I powered the 3.3v side from the BeagleBoard 5V supply and a 3.3v regulator.
You need to enable support for MCSPI and ADS7846 in the Kernel. There is some startup code for the ADS7846 you need to add in board-omap3beagle.c, which I copied from the board-omap3evm.c. You also need to update arch/arm/mach-omap2/mux.c to use SPI3 or SPI4. Then you need to update arch/arm/plat-omap/include/mach/board-omap3beagle.h to define the GPIO you will use for PenDown interrupt. Then you will need to update arch/arm/plat-omap/include/mux.h to reflect the changes you made to mux.c above.
Finally, you need to update u-boot so that the mux for SPI3 or SPI4 is set correctly.
After this, the touchscreen works fine.
Regards
John
Gerald
Hi Jerald
Thanks for the reply
Is the changes you suggested one shall do for integrating with your
recommended 4.3" touch panel could work for other resistive touch panel with
different size?
We need to use 15" resistive touch panel ( a must)
Thank you
On a quick note, this post with information board initialization I
guess it answers also my [off topic] question in
http://groups.google.com/group/beagleboard/browse_thread/thread/668c9e54715d4882#
Regading the LCD and TouchController for BB rev.C, I also have
designed a little LCD board with touch controller. The goal is to
utilize only the J4/J5 available signals and not any other expansion
header but it seems that there is something missing there, I need at
least one GPIO/Interrupt pin available on J4/J5 which has none. The
required GPIO/Interrupt is for the famous PenDown irq output of the
touch controller.
Yet again, all pins on J4/J5 are occupied but one is NC, the pin 12 on
J5. (Nice coincidence!)
I think that It might be possible to rewire it (pin12/J5) from the J5
header position with a small cable patch on BB to a GPIO/Interrupt
pin.
The best candidate IMHO is (AC3) GPIO175 but this pin is not available
to any other header and I'm not sure if it is possible to get it from
the underneath ballgrid.
Gerald, do you thing this is feasible?
If not I'll rewire it to an available GPIO that does gets exposed on
the expansion header. In such case is there any specific GPIO pin
recommendation for it?
Thnaks,
Christos
PS
At least consider this AC3->J5/Pin12 as an item in the wish list for
Rev.C4 :-))
Connecting a wire under an OMAP3530 to a .4mm pitch ball is not possible. I suggest you use a GPIO pin from the expansion header. Any of the GPIO pins should work.
Gerald
2009/6/10 sv1eia <sv1eia@gmail.com>
The change I suggested has no bearing on what touchscreens can be supported. It is only there to support touchscreen controllers that need an extra interrupt line into the processor. You need to verify the touchscreen controller that you wnat to add to the Beagle meets your requirements.
Gerald
If you look across all the different OMAP boards supported by the L-O, you can
get a feel for what is needed with different LCDs and different resolution.
Most of the OMAP2/OMAP3 boards use the same controller for the touch overlay.
wired) layout without having to deal with the driver details. But then I
haven't done a detailed analysis on the linearity of my board. It works well
enough to tap on buttons without tweaking. 