I have one of those 7" HDMI diplays from eBay, driving it with a Q1900 board running Ubuntu 20. I can write to the display using fbi
:
sudo fbi -a -T 1 --noverbose -d /dev/fb0 -t 5 --blend 1000 "${PICTURE}"
But the images seem to stay in the framebuffer, or the panel. When I write a second image, the display alternates between showing the two.
I've tried dd if=/dev/nul of=/dev/fbo
and just /dev/fbo
.
Neither work though. I haven't tried powercycling the Linux box, but powercycling the panel does nothing. If I have to reset the computer it's just not going to work for me.
Is there some command to flush the framebuffer, or is that not what I have to do?
TI
fbo
is not the same thing asfb0
, but I guess that might be just a typo? Also, there is no/dev/nul
: you might mean/dev/null
but it would not work as reading it will output just an immediate end-of-file condition. If you want to zero out something, use/dev/zero
as a source instead: it will output an infinite stream of zero bytes./dev/zero
to anything that has a finite size and you don't specify how much to write: after filling the target completely, it stops and reports there is no more space available. I just found some scripts you might use to test a framebuffer device in more meaningful ways than just zeroing it.