Code keep reboot after ESP32 connected to external board

[Rhafiq]

Hello guys,

I've got a problem where I'm testing my external board esp32 only using blinking led code, but the serial monitor shows it keeps rebooting after I connect esp32 to the external board. Does anyone know what happen? What makes it keep rebooting?

I attached the circuit diagram of my external board below

circuit.png (650.7 KiB) Viewed 1645 times

[ESP_Sprite]

What does your serial output say specifically?

[Rhafiq]

Arduino: 1.8.15 (Windows 10), Board: "ESP32 Dev Module, Disabled, Default 4MB with spiffs (1.2MB APP/1.5MB SPIFFS), 240MHz (WiFi/BT), QIO, 80MHz, 4MB (32Mb), 921600, None"

Sketch uses 198834 bytes (15%) of program storage space. Maximum is 1310720 bytes.

Global variables use 13248 bytes (4%) of dynamic memory, leaving 314432 bytes for local variables. Maximum is 327680 bytes.

esptool.py v3.0-dev

Serial port COM5

Connecting....

Chip is ESP32-D0WDQ6 (revision 1)

Features: WiFi, BT, Dual Core, 240MHz, VRef calibration in efuse, Coding Scheme None

Crystal is 40MHz

MAC: ac:67:b2:3d:47:04

Uploading stub...

Running stub...

Stub running...

Changing baud rate to 921600

Changed.

Configuring flash size...

Warning: Could not auto-detect Flash size (FlashID=0xffffff, SizeID=0xff), defaulting to 4MB

Compressed 8192 bytes to 47...



A fatal error occurred: Timed out waiting for packet content

A fatal error occurred: Timed out waiting for packet content





This report would have more information with
"Show verbose output during compilation"
option enabled in File -> Preferences.


This is the error message I got

[ESP_Sprite]

Warning: Could not auto-detect Flash size (FlashID=0xffffff, SizeID=0xff), defaulting to 4MB

That is not a good sign; means the ESP32 cannot communicate with the onboard flash. Does the devboard also do this when it's not in your PCB? If not, check if there is something shorting pins 16-18 or 20-22 to something; those pins must all be not connected.