T-SIMCAM and battery not working

[RogerParkinson]

I have a T-SIMCAM which is working just fine when I power it with the USB. It has a SIM7000E on it and that happily talks to my cell network. All good. It shows a blue light near the battery connector, a red status light on the modem and a flashing netlight also on the modem.

Now I want to power it from the battery. I plugged in a fully charged LiPo battery, nominally 3.7v but my multimeter shows 4.1v. Nothing happened. No lights, and the program I have flashed is clearly not running. Is there something else I need to do to enable powering this device by battery?

[RogerParkinson]

Still no answer here. I tried to ask on the LilyGo forum but all my attempts to register there give me a 504 error. I've looked at the schematic and I can see the battery delivers 3.3v to the ESP32 (and I measured that my battery does that), but there's no evidence the program is running.

[lewisxhe]

GPIO1 must be set to output during setup, and the output must be set to high level before the battery can be used. https://github.com/Xinyuan-LilyGO/LilyGo-Camera-Series/blob/17ea98b9b37734d08c80924c1630afda42c5e66a/examples/t_sim_cam_factory/t_sim_cam_factory.ino#L26

[RogerParkinson]

@lewisxhe Thanks so much for this. I've been struggling for days trying to figure out what was wrong. Adding those two lines turned it from not working to working. Definitely solves the problem.