Lopy4 will not boot via battery power on Expansion Board

  • I'm seeing a strange thing, the Lopy4 on Expansion 3 will not boot and run my program most of the time from battery. It runs just fine when powered by USB (code is in main.py). Basically if I power via USB there is no issue, but powering via battery rarely works. Maybe it will boot about 1% of the time when I hit the reset button from battery. I can start with USB then plug in a battery and then unplug USB and it runs fine until you hit reset again.

    Any ideas what to do? I just made sure the expansion board 3.0 and Lopy4 were on the latest firmware (stable). This puts a big damper in a demo I have in a couple of weeks where the Lopy has to be in a case on battery. Anything I should try? All jumpers are installed, and the batteries are just fine.

    I can move the Lopy4 to a Pysense and it runs just fine without making any changes. Very weird that it has trouble only when connected to the expansion board.

    Expansion board 3 is running 0.0.9 (fails to boot most of the time)
    Pysense is running 0.0.8 (boots every time)
    Lopy4 is running 1.18.1.r1 (stable)

  • Thanks, I ran the jumper from 3.3v to P8 and that solved the issue.


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