Just a quick follow up to note that now things are working very well, almost too good. When the espruino pico is in deep sleep and I remove the battery it doesn't reset, it continues to run for a short while, probably purely on the charge left in the capacitors! This unfortunately makes it hard to reset the device, which I sometimes have to do. I haven't checked how long it can run without batteries, but at least a few seconds.
Espruino is a JavaScript interpreter for low-power Microcontrollers. This site is both a support community for Espruino and a place to share what you are working on.
Just a quick follow up to note that now things are working very well, almost too good. When the espruino pico is in deep sleep and I remove the battery it doesn't reset, it continues to run for a short while, probably purely on the charge left in the capacitors! This unfortunately makes it hard to reset the device, which I sometimes have to do. I haven't checked how long it can run without batteries, but at least a few seconds.