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Hot!Using SPI interface to LCD rather than Graphics Module / MLA

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TomWr
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2017/02/08 14:08:56 (permalink)
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Using SPI interface to LCD rather than Graphics Module / MLA

Currently, I am in the process of doing a proof of concept with a prototype board based off the PIC24FJ256DA210.  For the POC we are using the LCD from the 4.3" LCD development board offered by Microchip.  In the future, we will likely move to a smaller 3.5" (or so) LCD display. 
 
Our POC has been a bit problematic.  The prototype board differs from the corresponding Microchip development board primarily by the external memory access.  PIC pins are needed for other functions so a fully-multiplexed address bus is used rather than the non-multiplexed bus as  implemented for the MHCP development board.
 
I anticipate the GUI will consist of 6-8 screens that are generally the same.  The header will remain relatively consistent.  The footer will contain navigation buttons.  The middle will change per screen and is NOT particularly dynamic.  No images.  I can probably get away with 4bpp.
 
A suggestion was made to use the SPI interface to the LCD instead of the graphics module, MLA, and RGB 565 parallel interface.  I am not even certain whether the SPI interface is plausible in terms of capabilities or throughput.  While a SPI is plausible for a smaller display, is SPI suitable for a 3.5 or 4.3 inch display?
 
What are design considerations to consider?  Experiences?  Caveats?  Successes?  I have my thoughts, but I am looking for input from others within the community.
 
Thank you,
Tom
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6 Replies Related Threads

    simong123
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    Re: Using SPI interface to LCD rather than Graphics Module / MLA 2017/02/08 14:37:54 (permalink)
    +1 (1)
    The datasheet states that the '210 supports 480x272 (WQVGA) at 4bpp with no external memory, leaving ~32k ram for your application, or 320x240 (QVGA) at 8bpp leaving ~20k.
    That would cut the external frame buffer SRAM out of your BOM and free up all the EPMP pins for your use.
    #2
    PStechPaul
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    Re: Using SPI interface to LCD rather than Graphics Module / MLA 2017/02/08 19:25:31 (permalink)
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    I don't know if it helps answer your question, but I used an Arduino UNO to drive a 1.8" TFT graphics display:
     
    https://www.youtube.com/watch?v=-A8L1Q07kmU
     
    It's been a while, but I'm sure it uses an SPI or I2C connection.
     
    I used the same display on another project, but also an Arduino Pro Mini:
     


     
    #3
    PStechPaul
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    Re: Using SPI interface to LCD rather than Graphics Module / MLA 2017/02/08 19:35:23 (permalink)
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    Tried to edit previous post with this, and "Access Denied" again.
     
    I also found an article on driving a 3.5" TFT LCD using an Arduino and an Adafruit library:
     
    http://www.instructables....SPI-In/step2/Software/

     
    #4
    CinziaG
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    Re: Using SPI interface to LCD rather than Graphics Module / MLA 2017/02/09 13:37:21 (permalink)
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    PStechPaul
     
    I also found an article on driving a 3.5" TFT LCD using an Arduino and an Adafruit library:
     




    Yeah I used them too with PICs, porting the Adafruit code Smile

    in 2018 you signed for your annihilation. in 2019 it will come ;) I promise
    my most wonderful creations here
    https://www.youtube.com/c...dPFRvtwsbSTXp6Sk6azGOQ
    #5
    levetop
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    Re: Using SPI interface to LCD rather than Graphics Module / MLA 2020/05/22 00:21:49 (permalink)
    +1 (1)
    Hello Engineers,
    I am Will from Levetop semiconductor.
    Our main product is LCD/TFT graphic controller.
    Support 8/16-bits MCU parallel interfaces, and SPI, I2C serial interfaces
    Built-in Ggeometric Drawing Engine: provide Point Drawing, Line Drawing, Curve Drawing, Ellipse, Triangle, Rectangle, Rounded Rectangle Drawing
    Built-in 2D Graphics Processing Unit: provide Magic Rotation, Reflect, PIP (Picture in Picture), Hybrid Graphics and Transparent Display
    Built-in 128Mbit Display Memory
    Support 16/18bits RGB type TFT Panel from 320*240 QVGA to 1280*1024 SXGA
    Built-in Standard ISO/IEC 8859 Fonts
    Built-in Two 16-bits PWM Timer
    Support SPI and I2C Master Interface
    Three Power Saving Modes: Standby,Suspend and Sleep mode
    Package: 128pin LQFP
    We have STM32/ST51C demo code open for developers, function libarary and Arduino Library available, too.
    Our product P/N as follow:
    LT7681 640*480 8/16bits/SPI/I2C
    LT7683 800*600 8/16bits/SPI/I2C
    LT7686 1280*1024 8/16bits/SPI/I2C
    LT7680A 640*480 SPI/I2C
    LT7680B 800*600 SPI/I2C
    LT7680+ 1280*1024 SPI/I2C
    any questions, feel free to contact us

    Levetop new develop board available now. It is based on LT7686/LT7381 chip. The board is very flexiable and friendly for developer, it support standard 40pin or 50pin TFT panel , and also support 8 bit, 16 bit. SPI. I2C MCU interface. Developer can use the jumper to choose the interface they need and use their most familiar MCU to test our chip.
    see below link to find more about Levetop develop board and demo kits.
    #6
    karan123
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    Re: Using SPI interface to LCD rather than Graphics Module / MLA 2020/05/23 02:58:40 (permalink)
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    levetop
    Hello Engineers,I am Will from Levetop semiconductor.Our main product is LCD/TFT graphic controller.Support 8/16-bits MCU parallel interfaces, and SPI, I2C serial interfaces
    Built-in Ggeometric Drawing Engine: provide Point Drawing, Line Drawing, Curve Drawing, Ellipse, Triangle, Rectangle, Rounded Rectangle Drawing
    Built-in 2D Graphics Processing Unit: provide Magic Rotation, Reflect, PIP (Picture in Picture), Hybrid Graphics and Transparent Display
    Built-in 128Mbit Display Memory
    Support 16/18bits RGB type TFT Panel from 320*240 QVGA to 1280*1024 SXGA
    Built-in Standard ISO/IEC 8859 Fonts
    Built-in Two 16-bits PWM Timer
    Support SPI and I2C Master Interface
    Three Power Saving Modes: Standby,Suspend and Sleep mode
    Package: 128pin LQFPWe have STM32/ST51C demo code open for developers, function libarary and Arduino Library available, too.Our product P/N as follow:LT7681 640*480 8/16bits/SPI/I2C
    LT7683 800*600 8/16bits/SPI/I2C
    LT7686 1280*1024 8/16bits/SPI/I2C
    LT7680A 640*480 SPI/I2C
    LT7680B 800*600 SPI/I2C
    LT7680+ 1280*1024 SPI/I2Cany questions, feel free to contact us
    Levetop new develop board available now. It is based on LT7686/LT7381 chip. The board is very flexiable and friendly for developer, it support standard 40pin or 50pin TFT panel , and also support 8 bit, 16 bit. SPI. I2C MCU interface. Developer can use the jumper to choose the interface they need and use their most familiar MCU to test our chip.see below link to find more about Levetop develop board and demo kits.


    Please post new thread..
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