[arm-allstar] HDMI and the PI

[Doug Crompton]

Ken,

 Yes, I have seen the HDMI power back feed the Pi. Best thing to do is
power them from the same source. In my portable node I power the HDMI
monitor from 12V in and then use a car adapter - 12V to 5V to power the
Pi.  Removing the single 12V supply powers everything down. The monitor can
be turn on and off by its power switch.


*73 Doug*

*WA3DSP*

*http://www.crompton.com/hamradio <http://www.crompton.com/hamradio>*




On Fri, Feb 9, 2018 at 12:33 PM, "Ken via arm-allstar" <
arm-allstar at hamvoip.org> wrote:

> Slightly off-topic:  I bought a small HDMI display to use with my RPI
> collection and found that, when I disconnect the 5 VDC from the RPI, the
> computer then tries to boot up using power supplied from the HDMI display.
> The re-boot is not successful since the HDMI seems unable to supply the
> voltage needed during part of the boot up sequence so it repeats
> endlessly.  I suspect that this has killed one of my RPI3’s.  So the
> question:  should this happen?  Has anyone else seen it? What do to?
>
>
>
> On a related note:  for any HDMI display - it seems that if you connect
> the display after the RPI is up and running, it is not recognized.  It’s as
> if the DHMI port is turned off.  Is there some option or setting that can
> force the HDMI port to be “on” or to recognize that something has been
> plugged in?
>
>
>
> Thanks
>
> Ken
>
> KE2N
>
>
>
> _______________________________________________
>
> arm-allstar mailing list
> arm-allstar at hamvoip.org
> http://lists.hamvoip.org/cgi-bin/mailman/listinfo/arm-allstar
>
> Visit the BBB and RPi2/3 web page - http://hamvoip.org
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.hamvoip.org/pipermail/arm-allstar/attachments/20180209/52e5514d/attachment.html>