does not appear to working after boot

All ESP32 boards running MicroPython.
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Joined: Sun Jun 28, 2020 12:04 pm

Re: does not appear to working after boot

Post by willip5 » Sun Jun 28, 2020 12:41 pm

Well this may or may not help but I am grateful the help on this forum since I have only had an ESP32 for a few days.
Having tried all the software fixes and failed I started, as suggested, to dig into the hardware issues. Thanks for the links by the way. I noticed that when I left the board off overnight it would reboot happily in the morning but for the first boot only. It was happy with a Ctrl+D or an EN boot at any time.
When USB is unplugged for a reboot the 3V3 pin dropped to zero as did the EN pin but the 5V line maintained about 0.3V stored on the power supply capacitors. By shorting this pin to ground via a 100k resistor for a few seconds the board would reboot correctly on power connection. You could add a discharge circuit as described in Fig 4 here, but on the 5V pin ... eet_en.pdf
or you could simply add a 100k resistor from the 5V pin to earth, although this does take a few seconds to clear the voltage.
Can anyone think of any disadvantage to this approach?

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