Pi 4 with Pi OS latest releases all updates. The screen size was wrong on first boot today. This is a Pi 4 I use for development experiments. The HDMI cable is unplugged every few weeks to experiment with a Zero or Pi 5. I use the same microHDMI socket. So maybe 50 inserts over the two years I owned the Pi 4. Today the Pi 4 decided the 2K screen is only 1K. What in a microHDMI socket would cause that?
Working with regular HDMI, I have test machines where the sockets work after hundreds of insertions. The microHDMI appears to be delicate by comparison.
The screen configuration -> resolution showed a list of 4 resolutions topping out at a 1024 * 768. I tested all the combinations of switching Pi and screen off and on plus reinserting the cable. Nothing worked. Then I inserted the cable into the other microHDMI socket and everything works. 20 resolutions to choose from and defaults to the full 2K.
What sort of error in a micro HDMI connection would cause it to partially work instead of simply not working? The 1K display worked perfectly. Right colours and everything. It read 4 of the possible screen resolutions but not all. Or maybe it read none and the 4 shown by the software is some sort of default list.
I have not found an understandable description of the HDMI startup to work out what the software does and where the error might occur.
As a last minute check, I reused the problem socket and it worked. The cable is the official cable. Either the cable or the socket is fragile. Has anyone had something similar? Was it the cable or socket? (I do not have a spare cable to test.)
Working with regular HDMI, I have test machines where the sockets work after hundreds of insertions. The microHDMI appears to be delicate by comparison.
The screen configuration -> resolution showed a list of 4 resolutions topping out at a 1024 * 768. I tested all the combinations of switching Pi and screen off and on plus reinserting the cable. Nothing worked. Then I inserted the cable into the other microHDMI socket and everything works. 20 resolutions to choose from and defaults to the full 2K.
What sort of error in a micro HDMI connection would cause it to partially work instead of simply not working? The 1K display worked perfectly. Right colours and everything. It read 4 of the possible screen resolutions but not all. Or maybe it read none and the 4 shown by the software is some sort of default list.
I have not found an understandable description of the HDMI startup to work out what the software does and where the error might occur.
As a last minute check, I reused the problem socket and it worked. The cable is the official cable. Either the cable or the socket is fragile. Has anyone had something similar? Was it the cable or socket? (I do not have a spare cable to test.)
Statistics: Posted by peterlite — Sun Oct 27, 2024 11:12 pm — Replies 0 — Views 40