Hello all,
I have a project going using a TinyZero processor, combo sensor board, wireling connect board with temp/press/humidity/VOC wireling and a TinyScreen on top powered by a 290MA battery. I have the code set up to read pressure, temperature and humidity on all three sensors (pressure and temp on the combo board, temp and humidity on the combo board, and temp, pressure and humidity on the wireling board). The display shows the internal (combo) board readings in metric units for 5 seconds, then in standard units for 5 seconds, then repeats for the external (wireling) sensor.
Everything works great, I can disconnect it from the computer and run it on the battery...until I power it off. When I turn it back on using the battery it won't boot up. Connecting it to the computer, pulling up the Arduino IDE (regardless of the sketch that appears, nothing gets downloaded) and opening the serial monitor boots it right up, and then I can disconnect it and it runs just fine on the battery.