W01 specsheet wrong
The "Minimum Recommended Circuit" on p 20 in https://docs.pycom.io/chapter/datasheets/downloads/w01-specsheet.pdf is not working. With this design the module will start booting, but halfway during the boot it will stop excuting. A pull up for the reset switch is needed (like https://docs.pycom.io/chapter/datasheets/downloads/oem-universal-schematic.pdf).
Learned the hard way...