Power only using USB cable? Turn off modem when RPi is halted or shutdown

Raspberry Pi Network HATs 3G/4G&LTE Base HAT
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Is there any recommended hardware or software hack or modification to keep LTE HAT turned off upon sudo shutdown even if RPi is still with power?

Option 1: Looking at the schematic, the only way I’ve found so far is to not mount the 40pin header PIN and use only USB cable, but I loose all GPIO functionalities.
Option 2: Cut PIN2 and PIN4 (5V lines) traces so that RPi header does not pass 5V over the 40pin connector.

I also tried AT+QPOWD=1 so that the module is turned off before shutting down, but upon shutdown, the module restarts.

Setting GPIO26 HIGH will only turn off the modules while the pin is high, so upon RPi shutdown, the module restarts.

any ideas? If not, can you add a jumper to the 5V lines in your next version so that the user can choose to power the module over the USB cable?

1 Like
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I also tried AT+QPOWD=1 so that the module is turned off before shutting down, but upon shutdown, the module restarts.

I tried this and after a few seconds the module boots back again even if I don’t turn off the Raspberry.
How to ensure that the module will not turn back on?

[10:47:58:032] AT+QPOWD=0␍␊
[10:47:58:038] OK␍␊
[10:47:58:038] ␍␊
[10:47:58:038] POWERED DOWN␍␊
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@santiago,

Have a look at this readme, it may help you out.

https://raw.githubusercontent.com/raspberrypi/firmware/master/boot/overlays/README

Search for “dtoverlay=gpio-shutdown”

and it will give you details on setting a pin state (in your case 26) that should be retained after shutdown.

Shawn