HATs and other add-ons • Re: PI 5won't recognize DS3231 RTC module

I'm surprised to hear that this config.txt works at all on a Pi5! You're using FKMS while Pi5 relies in KMS -> would espect yoi have no HDMI output at all.

OP is not using FKMS on the Pi 5.

Code:

[pi4]# Enable DRM VC4 V3D driver on top of the dispmanx display stackdtoverlay=vc4-fkms-v3dmax_framebuffers=2#hdmi_enable_4kp60=1hdmi_enable_4k=1gpu_mem=256max_framebuffer_width=3840max_framebuffer_height=2160[all]#dtoverlay=vc4-fkms-v3d

The first dtoverlay for fkms is in a [pi4] block, so won't affect a Pi 5.
The second is commented out.

Next comes the question if that kernel has support for your RTC. Is the overlay (i2c-rtc) applied and does it has the RTC (ds3231) as a valid parameter?

This is a very good point and was going to be my next question. Looking at the kernel config to see if CONFIG_RTC_DRV_DS1307 is set (the module used for the DS3231) would be the next step.

Statistics: Posted by rpdom — Wed Feb 19, 2025 8:20 am

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