ESP32 programming circuit not going into program mode automatically with UMH3N

[pietnl]

I recently had a prototype made that used a FT232RLSSOP and UMH3N for Usb to serial and programming.

The circuit looks like this:

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SHOT1.PNG (3.44 KiB) Viewed 3283 times

The attachment SHOT1.PNG is no longer available

I thought this would be enough to automatically program the ESP32 for the arduino IDE, but I'm probably missing something.

I get the following error:

Code: Select all

esptool.py v2.6
Serial port COM8
Connecting........_____....._____....._____....._____....._____....._____....._____

A fatal error occurred: Failed to connect to ESP32: Timed out waiting for packet header

I also have a reset button on the board which just connects EN to GND. When I press that button (a few times) when I see "Connecting........_____", the programming actually starts and works.

Any idea where I'm going wrong?

[ESP_Sprite]

The 1K resistor pullup for EN seems a bit too strong to me... I'd replace that with an 10K, perhaps that helps.