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STM32F429 WVGA LCD

Former Member

I'm looking to drive an 800x480 LCD using an STM32F429 and the STemWin graphics library, due to the other peripherals needed from the chip, the SDRAM will most likely be limited to 16-bit. Could this be a serious performance bottleneck? And are there examples of this setup working effectively?

  • 0

    look at my smart solder reflow oven, its 800x480 AMOLED with capacitive touchreen, and you can't run STemWin, it will be very chopy ( if you need touchcreen )
    And yes, it is STM32F429Z running at 200MHz with 2MB 10ns SRAM, and this screen use lot of CPU time. So only way to get responsive UI, is to make one yourself, like i did

     

  • 0 in reply to Kilohercas

    Thank you for the quick response!

     

    If it's not too much trouble could you answer a few specific questions about your implementation? We're planning on LCDs with a 24-bit RGB interface and will probably be limited to a 16-bit wide SDRAM, in your application what interface is the OLED screen driven by? And what's the bus-width access to the SRAM? We're not planning on implementing any kind of touch-screen capability, was it just this feature that caused the choppiness in STemWin, or is it just a case of too much data throughput?

     

    Thanks in advance.

  • 0 in reply to Former Member

    AMOLED screen use RGB565 interface, so it matched SRAM bus width of 16b. You can always run your 24b system by not connecting LSB colors,
    If you add touschreen, any slider, or mouving part will be very choppy, because you will have like ~6FPS real data update ( while screen VSYNC was 30FPS). I have STemWin ported to run with this screen, if you only interested in static data, and changing text, it will work ok

  • 0 in reply to Kilohercas

    Thanks for the information, we've found it extremely helpful. It appears we might be trying to push the chip just a little too far, as although we're not planning on touchscreen capability some transitions and graphical ui elements like those provided in STemWin would probably come in handy.

     

    Thanks again for the help.

  • 0 in reply to Former Member

    I have few PCB left from this project. to make it work you only need SRAM, LDO, STM32F429ZI, AMOLED screen and few other parts.
    (since i use OSH park, i get 3 boards default)