Oh, I see that ST7789 boards do not expose VSYNC. So whatever they (Sitronix) suggest in the datasheet can only be done if you can read a status register that has a VSYNC bit and sync to that. Otherwise, you'll probably see some tearing.
I guess you can check or test for tearing already, since you are already writing full frames to the board. If it's tearing but it doesn't bother you, then you can just write whenever you want. But compared to phone displays these days, tearing might be distracting and undesirable.
[Edit] Reading further, the TE (Tearing Effect) pin provides the sync signal to the MCU. But from a quick search, it looks like only Adafruit breaks it out.
I guess you can check or test for tearing already, since you are already writing full frames to the board. If it's tearing but it doesn't bother you, then you can just write whenever you want. But compared to phone displays these days, tearing might be distracting and undesirable.
[Edit] Reading further, the TE (Tearing Effect) pin provides the sync signal to the MCU. But from a quick search, it looks like only Adafruit breaks it out.
Statistics: Posted by katak255 — Mon Feb 24, 2025 3:12 am