Beaglebone Black does not startup automatically when power is supplied

Hi all,

I have a BeagleBone Black, Rev A5B which I boot from the micro SD card with Debian 10 (Buster). If I shutdown the system with “shutdown -h now”, it switches off but if I then switch off and switch on the 5V power (via the barrel jack), the board does not boot up again. Only after I manually press the power button it boots again. Is there a way to configure it to boot without a manual key press once power is back?

Best regards,
Reiner

Possibly your 5V power supply is not coming on in a way that the
on-board distribution system is detecting it correctly. Does the power LED
come on?

  My revC with a 5V 2A wall-wart supply, stuck into a wall socket
controlled with a lamp switch, powered up nicely when I flipped the wall
switch.

The power supply is on all the time. I just switch the 5V on/off with a switch. After switching on, the power LED is not on. If I then press the Power button, the power LED switches on and the board boots.

What power supply with a switch are you using? Did you add a switch inline with a barrel jack power supply or is it part of the power supply adapter you are using?

Cheers,

Jon

So you aren't switching the power supply, but somehow are toggling some
sort of inline switch on the power lead?

<shudder>

  Switch bounce could be scaring (if not scarring) the PMIC -- if it sees
a series of up/down transitions from the bounce (use a storage tube or
digital oscilloscope with probe and ground held to the end&side of the
barrel connector, and flip the switch -- if you see ___|-|_|-|_|---- at the
start of the sweep, you have switch bounce). Pushing the power button is
taking place after the voltage stabilized. Possibly fitting a capacitor
between the power leads (value TBD -- large enough to smooth out bounce,
but small enough to not cause the opposite problem of a too slow
transition) would help.

I use a Mean Well ELP-75-5-Cpower supply. The switch is inline with the barrel jack power cord.

https://www.thingiverse.com/thing:4323103
https://www.thingiverse.com/thing:4543253
https://www.thingiverse.com/thing:4326381

I have a Raspberry Pi on another port of that setup where it works fine. Just the BeagleBone Black doesn’t want to start without another manual keypress.