2025-10-04 2:36 AM
I would like to add a custom resolution hdmi display (1024x600) to my STM32MP257F-DK board is it possible as the dmesg output is as follows
[ 930.525408] [drm:drm_helper_probe_single_connector_modes] [CONNECTOR:32:HDMI-A-1]
[ 930.590130] stm32-display 48010000.display-controller: [drm:update_display_info.part.0] [CONNECTOR:32:HDMI-A-1] ELD monitor
[ 930.590170] stm32-display 48010000.display-controller: [drm:update_display_info.part.0] [CONNECTOR:32:HDMI-A-1] ELD size 20, SAD count 0
[ 930.590208] stm32-display 48010000.display-controller: [drm:update_display_info.part.0] [CONNECTOR:32:HDMI-A-1] ELD monitor
[ 930.590223] stm32-display 48010000.display-controller: [drm:update_display_info.part.0] [CONNECTOR:32:HDMI-A-1] ELD size 20, SAD count 0
[ 930.591397] [drm:drm_mode_debug_printmodeline] Modeline "1024x600": 60 49000 1024 1072 1168 1312 600 603 613 624 0x48 0xa
[ 930.591421] [drm:drm_mode_prune_invalid] Not using 1024x600 mode: CLOCK_RANGE
[ 930.591433] [drm:drm_mode_debug_printmodeline] Modeline "800x450": 60 27759 800 816 896 992 450 451 454 466 0x0 0x6
[ 930.591450] [drm:drm_mode_prune_invalid] Not using 800x450 mode: CLOCK_RANGEThe display shows CLOCK_RANGE, is there any possible way to add a custom resolution if it is not present by default in the edid data.
2025-10-07 6:59 AM
Hello @Samip_veer ,
Please can you take a look at this wiki article: https://wiki.st.com/stm32mpu/wiki/How_to_display_on_HDMI
I think it can highlight some points you are looking for.
Kind regards,
Erwan.
2025-10-09 11:51 PM
Dear @Erwan SZYMANSKI
Thank you for your reply i had aldready studied the article and also checked various community discussion but the problem if CLOCK_RANGE means i need to set the clock frequency so that the pixel clock frequency matches with my device, can you help me with that as i did not find any relevant material in the article.
2025-10-13 12:01 AM
Hi @Samip_veer ,
Did you already check this answer from Antonio ? https://community.st.com/t5/stm32-mpus-products-and-hardware/what-are-the-criteria-for-modetest-to-accept-a-modeline/td-p/268952
Did you try to activate debug too to get the exact clock value you get VS the one that is expected ?
Kind regards,
Erwan.