LCD screen

Discussion in 'The Projects Forum' started by KansaiRobot, Oct 5, 2015.

  1. KansaiRobot

    Thread Starter Active Member

    Jan 15, 2010
    318
    5
    Hello and thanks always.

    As I mentioned in other thread I am interested in developing with a touch panel.
    This thread though is a different although related thing.
    Putting aside the "touch panel" controlling issue, I would like to ask about how to control and do GUI on a LCD screen

    (I am talking about big size LCD- as in 3.2 inches or 4.3 or 7 inches, not text based two lines ones)

    Do they necessarily need controllers? For example I read in one spec about the ST7781 driver, but I am not limiting my question to this.

    Any example on how to control this with a microprocessor -say PIC (but can be others... although not arduino or raspberry pi, I am going more for PICs or AVRs )

    Thanks a lot in advance
     
  2. GopherT

    AAC Fanatic!

    Nov 23, 2012
    5,979
    3,690
    Most LCD screens have a controller built into the panel. Whether it is a 16x2 text display or a touch screen. A raw LCD is rarely sold because then the user would need to buy the zebra connectors to interface the display with the chip - and then interface the chip with the Microcontroller.

    Here is another thread about a touch screen recommendation.

    http://forum.allaboutcircuits.com/threads/easy-to-use-graphical-lcd-tft-display.115701/
     
  3. Art

    Distinguished Member

    Sep 10, 2007
    785
    61
    Typically a graphic (or any LCD) will have a controller,
    or your micro might need hundreds of outputs to multiplex all those pixels.
    The controller will also have enough video RAM to hold a display while your micro prepares the next screen,
    which would not naturally happen with your micro.... so you then have double buffering.
    I tend to avoid products that add a serial controller, which will slow down performance.
     
  4. KansaiRobot

    Thread Starter Active Member

    Jan 15, 2010
    318
    5
  5. ISB123

    Well-Known Member

    May 21, 2014
    1,239
    526
    It doesn't have a controller,unless they mean just V-sync,H-sync,rgb and that stuff.It uses parallel RGB interface which is going to be hell to get running since it requires yet again another driver IC so you can talk to the microcontroller and that microcontroller has to be a hefty one.
     
    KansaiRobot likes this.
  6. KansaiRobot

    Thread Starter Active Member

    Jan 15, 2010
    318
    5
    Thank you . I noticed that their other models (3.2 and 2.2 inches) do mention controllers (ILI9325 and BD663474) but the 4.3 does not....
    ummmm guess I will have to keep looking :(

    EDIT:Yes, apparently they need "FPGA or FTDI FT800 chip"
     
    Last edited: Oct 6, 2015
  7. KansaiRobot

    Thread Starter Active Member

    Jan 15, 2010
    318
    5
  8. KansaiRobot

    Thread Starter Active Member

    Jan 15, 2010
    318
    5
    Quick question.

    Reading about LCD manufacturers I have the feeling that each one of them have their own set of libraries that only work with their products and that there is no standard way to control a LCD GUI

    Am I getting this wrong?
     
  9. KansaiRobot

    Thread Starter Active Member

    Jan 15, 2010
    318
    5
    If a TFT LCD has a 8 bit interface, how do you send 16 bits data to it??
     
Loading...