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Re: hdmi wake up

Posted: Mon Nov 08, 2021 12:07 pm
by m1cfk
a few reasons for my use of hdmi.

wallboard, lastqso is great.

but in past pi has fell off the network for no reason... i was able to reboot it via rf dmr 8 code. i wanted to see via hd ssh what it was doing, but couldnt.
Thats since stopped happening the falling off network fully.

but occasionally it looses itself again....but i can connect to it by its ip, yet looking at the log page, it says something about no network, unable to connect to master...yet if theres no net, how have i connected....again a reboot is the only fix.

i need to retry these 2 commands, from web ssh.
i was sending a lot of commands, so i dont know if these 2 did wake it up, or a combination of random commands. but these 2 were last used, and then it woke up the screen at the normal login prompt when i was able to login by keyboard.

tvservice -p ; setterm default

Re: hdmi wake up

Posted: Wed Nov 10, 2021 8:00 am
by n7ekg
Pi-Star is designed to NOT have a monitor attached or even needed, therefore there is NO HDMI "display code" or even support really.
I'm not talking about blanking the screen - please re-read what I wrote. I'm talking about waking the screen up. Whether or not Pi-Star is designed to be headless or not has nothing to do with it - the code is still in the kernel to drive the HDMI port.
...thats why screen blanking was invented...
Thanks for the history reminder, but quite unnecessary. I am quite aware of the history behind screen blanking - I wrote some of the original ASM code to power up and down monitors (put them in "sleep" mode) when I worked for EDS in the mid-80's, and I am also aware of the hardware limitations of setting screen modes.

Please see https://www.raspberrypi.com/documentati ... i_blanking for an interesting caveat when running on a Pi 4.

Re: hdmi wake up

Posted: Wed Nov 10, 2021 8:17 pm
by n7ekg
AGAIN this is NOT something that Pi-Star has modified, so WE don't support it.
I made the comment because someone else had run up against the problem, and I was hoping that someone had found a solution. There was NO implication that this was or wasn't a Pi-Star issue.