Pi4 won't boot when BCM17 pulled high

Question

I have a boot issue with a system consisting of

Everything works fine with BCM17 when the system has booted. I can read the pin and it reflects the status of my external 12V.

But when I first apply 12V and then the Pi supply voltage, the system won't boot.

the system won't boot. what happens instead? what happens without the "official" (why is it in quotes) touch display? — Jaromanda X, Commented Jan 26, 2021 at 9:17
by "what happens instead" I mean, does the activity light flash? does anything at all appear on the display? etc etc — Jaromanda X, Commented Jan 26, 2021 at 9:22
What happens instead: Red led constantly on, green led constantly off. Display shows nothing. No SSH access from outside. When I disconnect both the FPC cable and the power jumper cables that came with the Display and power up, the behavior is the same. Seems not to be display-related. — Simon, Commented Jan 26, 2021 at 16:36
Oh, so the green led doesn't even flicker at all. Do you need/have any overlays loaded for this "custom shield"? — Jaromanda X, Commented Jan 26, 2021 at 22:27
Exactly. The shield only uses GPIOs und the I2C. I activated the latter using raspi-config. The only line starting with dtoverlay in '/boot/config.txt' appears to be DRM related: dtoverlay=vc4-fkms-v3d — Simon, Commented Jan 27, 2021 at 14:18

Simon · Accepted Answer · 2021-01-29 09:45:49Z

0

My bad, I was drawing too much current from the pin. Apparently this led to the startup issue.

answered Jan 29, 2021 at 9:45

Simon

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