I just got back my custom PCB using the ESP-WROOM32 module. I'm using an FTDI with it. GPIO0 is connected to ground via a jumper.

enter image description here

I made a very stupid mistake and forgot to include a pushbutton and pull-up for the EN pin.

Anyways - the chip boots up (I can see from serial monitor in the Arduino IDE) and I can also almost flash to it but it fails after writing with the error "Timed out waiting for packet header". Is it due to the fact that my EN isn't being pulled down to ground at boot? It's going to be super difficult to get a pull-up in there now.

enter image description here

My Arduino IDE settings are as follows: enter image description here

What's going wrong?

  • \$\begingroup\$ Check out the documentation on the usage for esptool; specifically the section on automatic bootloader. Seems like you need to wire up both EN and GPIO0 to the RTS/DTR pins on the FTDI chip. \$\endgroup\$ – Matt Clark Jul 4 at 1:31
  • \$\begingroup\$ EN is 'enabled'. it can't be LOW at boot because boot doesn't happen until EN doesn't have 3.3 V. the write is not finished. it is only one small part. you should first learn the MCU before making a PCB with it \$\endgroup\$ – Juraj Jul 4 at 15:25
  • \$\begingroup\$ @Juraj "boot doesn't happen until EN doesn't have 3.3 V" - If you look at the screenshot I had in my original post - the device clearly boots up - "waiting for download" while EN is at a constant 3.3V. \$\endgroup\$ – AlfroJang80 Jul 4 at 18:22

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