ESP32-WROOM-32U bare module boot-up problem

[davefes]

In order to get these bare modules to flash and to run I needed to do the following:

• add a 100nF cap from IO0 to ground, as found on the boot button DevKitc_V4
• add a 1uF cap from EN to ground, a 10K to 3V3 and a EN button

The problem is after the chip is powered-up I have to hit the EN button to get it into the correct mode. I would like it to power-up like the DevKitc_V4 board does, ie without having to hit the EN button first.

Anybody figured this out?

[davefes]

Thanks to Google there was a suggestion that GPIO0 needed a pull-up as well. Another 10K to 3V3 works with rshell ... at least.
The real answer is further down the thread.

[davefes]

Spoke too soon ... another two boards and I can't even erase the flash. There must be another condition that needs to be met.

The only other connections to the chip module are TX, RX. ground and a 3V3 supply capable of 1A or more.
Both EN and GPIO0 pulled up to 3V3.

Appreciate any suggestions.

[davefes]

Thanks to:
https://www.esp32.com/viewtopic.php?t=5682
which states:

when the dots and dashes start, press both EN and BOOT, then release EN, wait until the dots and dashes stop, then release BOOT.

Seems this only needs to be done to erase the flash as I did not have to do this to flash the image or to use rsusb.