Hi,
I'm working with BT817 (STM32 + EVE-MCU-Dev) and multiple displays. On a 480×272 panel (PH480272T015-IAA15), everything works reliably — ASTC images from flash, fonts, stable rendering.
After moving to larger panels (MI0700COT-1 800×480 and LMT070WS027C 1024×600), I'm seeing unstable and non-deterministic behavior. The initialization and overall approach are analogous, but results are inconsistent. Depending on reset, the display may work correctly or show flickering, corrupted fonts/images, or ghosting (previous screen content partially visible).
Importantly, the issue also occurs with minimal code using only CMD_TESTCARD(), which is sometimes stable and sometimes shows artifacts. This suggests the problem is not related to display lists or assets.
Given that even testcard is affected, I suspect RGB timing (porches/sync), PCLK (frequency/polarity), CSPREAD, possible underruns, or signal integrity issues at higher pixel clocks. I've tried multiple timing configurations (both from datasheets and library defaults) as well as different PCLK settings, but without consistent improvement.
Has anyone seen similar behavior when moving from 480×272 to higher resolutions? Are there known-good timing settings for these panels?
Additionally, I have a few related questions:
Any suggestions or best practices would be greatly appreciated.
Thanks!
I'm working with BT817 (STM32 + EVE-MCU-Dev) and multiple displays. On a 480×272 panel (PH480272T015-IAA15), everything works reliably — ASTC images from flash, fonts, stable rendering.
After moving to larger panels (MI0700COT-1 800×480 and LMT070WS027C 1024×600), I'm seeing unstable and non-deterministic behavior. The initialization and overall approach are analogous, but results are inconsistent. Depending on reset, the display may work correctly or show flickering, corrupted fonts/images, or ghosting (previous screen content partially visible).
Importantly, the issue also occurs with minimal code using only CMD_TESTCARD(), which is sometimes stable and sometimes shows artifacts. This suggests the problem is not related to display lists or assets.
Given that even testcard is affected, I suspect RGB timing (porches/sync), PCLK (frequency/polarity), CSPREAD, possible underruns, or signal integrity issues at higher pixel clocks. I've tried multiple timing configurations (both from datasheets and library defaults) as well as different PCLK settings, but without consistent improvement.
Has anyone seen similar behavior when moving from 480×272 to higher resolutions? Are there known-good timing settings for these panels?
Additionally, I have a few related questions:
- What is the practical maximum size/resolution of images that can be displayed smoothly on BT817 (especially when using ASTC 4×4 or assets from flash)?
- In flash FULL mode, is the SPI clock fixed by EVE, or can it be increased to improve throughput?
- For very large fonts (~400–500 pt), EVE Asset Builder seems to hit limits (glyph width issues) — what are recommended approaches to handle large fonts while keeping full character support?
Any suggestions or best practices would be greatly appreciated.
Thanks!