M5Paper - Flickering when updating screen



  • I tried to display some text or graphics with both Arduino IDE and M5Flow(python).
    When using an Arduino, it can update the screen without flickering using the M5EPD. But python doesn't.
    Is there a way with python to update only one character, not the whole screen like M5EPD? Even using "partial show", the small area blinks.
    And one more thing, is there a way to prevent the screen from flickering when waking up the device after executing m5.shutdown() on the Arduino?



  • Hello @BBulMushroom

    under Arduino it is possible to update the screen after waking up from shutdown w/o flickering. It's a bit tricky as the previous content (e.g. what was on the screen before the shutdown) needs to be available after waking up again as it needs to be 'drawn' again before the new content can be applied, else the previous content is not removed and pixels are just added over each other. In this example this is achieved by using M5Papers EEPROM to store the current value of the count.

    Thanks
    Felix



  • Screen redraws are normally slow because of the e-ink specification, flicker is normal. If your not getting it on arduino you may be forgetting the required draw delay and overdriving the screen refresh rate!



  • Hello @ajb2k3

    thank you for the valuable reminder about the screen refresh rate. My above example is meant to show that it is possible to do a refresh w/o flickering even after a shutdown.

    Thanks
    Felix