Serial Exception Error with SparkFun Thing Plus - ESP32-S3 (Write Timeout on COM Port)

Development Boards ESP32
1

Hi everyone,

I’m encountering an issue while trying to upload a sketch to my SparkFun Thing Plus - ESP32-S3 board. Here’s the error message I’m receiving:

Sketch uses 301949 bytes (23%) of program storage space. Maximum is 1310720 bytes.
Global variables use 18660 bytes (5%) of dynamic memory, leaving 309020 bytes for local variables. Maximum is 327680 bytes.
esptool.py v4.6
Serial port COM38
Connecting…
A serial exception error occurred: Write timeout
Note: This error originates from pySerial. It is likely not a problem with esptool, but with the hardware connection or drivers.
For troubleshooting steps visit: Troubleshooting - ESP32 - — esptool.py latest documentation

I’ve reviewed SparkFun’s documentation for the board: Arduino Examples - SparkFun Thing Plus - ESP32-S3

Here’s what I’ve tried so far:

  1. esptool Version: Initially, I used esptool v4.6 (per the SparkFun docs). After receiving the error, I updated to the latest esptool v4.8.1, but the error persisted.
  2. Board and Port Setup:
  • Board: Selected “ESP32S3 Dev Module”
  • USB Mode: Hardware CDC and JTAG
  • USB CDC on Boot: Enabled
  • Upload Mode: UART0 / Hardware CDC
  • PSRAM: QSPI PSRAM
  • Port: COM38 (verified in Device Manager)

All settings seem correct, and the COM port is the same as listed in Device Manager.

I’ve double-checked hardware connections, tried different cables, and reset the board multiple times, but no luck. If anyone has encountered this issue and found a fix, I’d appreciate your insights.

Thanks in advance!

2

Just to make sure: do you press the “reset” button followed by “boot” , then release “reset” and wait until the upload starts. Once started release the “boot” button ?

3

So I want to be writing to my flash during bootloader mode? And do I always need to flash like this?

4

That is the way it works on ESP32…

5

Thanks for the info…