No hdmi signal on Pi4 using "hdmi1" after updating

[richieeee]

Hi

I got the Pi4 kit from the shop. Booting the Pi4 worked, but then after updates the Pi didn't work, no hdmi signal.

Reflashed the latest Pi buster image, 2019-06-20 release, on to the card. Booted again, updated again, lost hdmi again.

I was told by Pi store staff the Pi4 kit included a 32gb card, which turned out to be a 16gb. So I wasn't sure if the card was faulty.

However, I have discovered that the cause seems to be if you use hdmi1 on the Pi after updating, then you lose hdmi output from hdmi1.

I tried hdmi0, the one nearest the usb-c power input and it worked. However if hdmi1 plugged in, booting doesn't work.

Rich

[b3lt3r]

As noted on my thread - many thanks for this and proving I wasn't insane....

Just to note for me at least, with one monitor used in port 1, the boot was actually working - I was able to connect via SSH - it was purely the HDMI output was suppressed.

[richieeee]

hdmi1 should work though. A colleagues Pi4 works on hdmi1 after the update. Their sdcard in my Pi4 fails on hdmi1. Also prevents dual screen

So perhaps a hardware fault. Or pernickety hardware.

[richieeee]

I've got both hdmi sockets working now after adding

core_freq_min=500

to config.txt

As per https://github.com/raspberrypi/firmware/issues/1159

[PeterO]

It seems that the code for HDMI-1 is sensitive to the state of the monitor. If I turn everything on together (Pi + Monitors) it boots OK.
If the monitor on HDMI-1 has gone into standby mode (because there is no video) then the boot will fail.

PeterO

[jamesh]

It seems that the code for HDMI-1 is sensitive to the state of the monitor. If I turn everything on together (Pi + Monitors) it boots OK.
If the monitor on HDMI-1 has gone into standby mode (because there is no video) then the boot will fail.

PeterO

Hmm, that's interesting....perhaps something odd with getting the EDID, which should work when powered down, but maybe isn't.