Tachyon boot from GPIO power

Tachyon
1

The Ubuntu 20.04 Caveats page mentions being unable to boot from USB power alone, but it seems to imply that powering the board from the 5V header without a battery connected should work. Is this the case? I’m running into the same issue where the board cannot boot from the 5V header alone.

I watched the header voltage on a scope, and it does drop to a little over 4V for a brief period of time. This dip lasts about 500us before the board aborts its boot process and returns to the shutdown state. My power supply should be able to source enough current, so I may try adding a capacitor to see if I can get rid of the transient dip.

2

You should be able to boot from HAT 5V if there is sufficient current (5 amps @ 5 VDC).

See power requirements.

1 Like
3

Thanks for clearing that up for me. I added the cap, and the board seems to be booting fine for now. But the power supply will definitely be my first suspect if I encounter any more issues.