ESP32 Forum

Hardware:
Board: ESP32-WROOM-32D
Core Installation/update date: ?
IDE name: Arduino IDE/esptool.py
Flash Frequency: 40Mhz
Upload Speed: 115200
Flash size: 4Mb

Description:
Since 2 days, I try to understand why I can't program my 4 esp32 wroom 32D that I received. I am using Arduino IDE and an FTDI adapter to program. I did several tests, everything works correctly when I program an esp-WROOM-32 but as soon as I want to program the 32D it does not work.
AT the end of the programming I have this:

esptool.py v2.6
Serial port COM7
Connecting........_____....._____....._____....._____....._____....._____.....____An error occurred while uploading the sketch
_

A fatal error occurred: Failed to connect to ESP32: Invalid head of packet (0xF0)

My PCB and ESP32-WROOM-32D failled:

https://github.com/Christophe45/ESP32-L ... oom-32.jpg
My PCB and ESP32-wroom-32 working:

https://github.com/Christophe45/ESP32-L ... oom-32.jpg
My FTDI :

https://github.com/Christophe45/ESP32-L ... daptor.jpg

I press the right buttons to program. I know my ESP-32-wroom-32D is working fine because when I use and other programmer it working fine
my other programmer:
https://github.com/Christophe45/ESP32-L ... mage0.jpeg

My sketch is simple:

void setup() {
Serial.begin(115200);
}

void loop() {
Serial.println("Going to sleep now");
delay(1000);
}

Many thanks in advance for your help

Hi,

try searching for "Strapping Pins" in the documentation of the ESP32.
The "other Programmer" already has resistors pulling Up the Enable-pin and IO0 (RST/PROG)
Guess this is what you're missing.

try google-images of "esp32 boot pins" you'll find plenty of wiring examples
or try to program the ESP32 outside your "other programmer", you will find out that you need to connect 6 wires in order to get it working: 3V3, GND, EN, IO0, RXD, TXD

Best Regards
Collin