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24 bit parallel display driver

Former Member

I want to use a 24-bit parallel interface to an LCD touchscreen display. There are lots of them out there, more than and cheaper than other interfaces.

http://www.newhavendisplay.com/tfts-50-tfts-c-1_595.html

I want to reserve the HDMI for external use.

Is there a petalinux driver for these displays?
If not, what would be required?

Thanks,
Emmett

  • 0

    Hi Emmett,

    It's an interesting application but would consume a lot of I/Os (I estimate somewhere around 27).  However, I am not aware of any existing drivers to support this.  Although it should be possible to implement the parallel RGB display IP in fabric but I would estimate that it would take some work.

    Here is one suggested approach:

    It may be possible to leverage our ALI3 standalone reference design and modify it to remove the OSERDES output along with the serial RGB-A mapper and bolt the RGB output directly to OBUFs.  This would give you a way to generate panel timing and pixel clock for your display panel while providing the AXI VDMA video data pipeline from DDR3 space into the Programmable Logic.

    There is also a standalone application provided with the ALI3 reference designs which you could use to drive a simple frame buffer to validate your IP modifications.

    Once you have that in place there are some modifications needed to the kernel to adjust the DRM display subsystem to match the panel resolution.

    Another possible approach:

    I have also heard (but not confirmed myself) that the Xylon logicBRICKS IP at one point had a parallel RGB output that you could tap into so if you are looking for something that has a lot of Linux support, that may be the way to go.

    http://www.logicbricks.com/logicBRICKS-IP-Library.aspx

    Regards,

    -Kevin

  • 0 in reply to zedhed

    Thanks Kevin,

    With a little more research I found other touchpad displays that use the FTDI FT801 or FT813 interface chip w/ SPI interface.

    This relieves a lot of the details pertaining to the display itself.

    I still need to get the Linux to FT8xx firmware together,  although FTDI has some examples.

    Thanks,

    Emmett