IOTHUB SOFTWARE · 02

ESP32 Board Setup in Practice

ESP32 setup is more than adding a URL. Board family, flash size, upload speed, USB driver, and boot mode must match the actual board.

Key TermsESP32Boards ManagerCP210xSerial MonitorTFT_eSPI

Arduino IDE knows Arduino boards by default. To use ESP32, you add one setting. You only need to do it once.

Add ESP32 to Boards Manager

Open Arduino IDE.
Mac: Arduino IDE → Settings. Windows: File → Preferences.
Paste this URL into Additional boards manager URLs:

code

https://raw.githubusercontent.com/espressif/arduino-esp32/gh-pages/package_esp32_index.json

Press OK.
Click the Boards Manager icon on the left.
Search esp32.
Click Install on esp32 by Espressif Systems. It is large, so it can take a few minutes.

Select Board

Connect ESP32 by USB, then:

Tools → Board → ESP32 Arduino → ESP32 Dev Module.
Tools → Port → choose the ESP32 port. Windows often shows COM3; Mac often shows /dev/cu.usbserial-XXXX.
Tools → Flash Size → 4MB (32Mb).

Driver Issue

Windows: If Device Manager shows !, the CP210x driver is missing.

Download and install the CP210x USB to UART Bridge driver.

Mac: It usually works already. If not, install the same CP210x driver.

Common: Make sure the USB cable supports data. Charging-only cables are a very common reason ESP32 is not detected.

Serial Monitor

Use this to see what ESP32 is doing after uploading code.

Tools → Serial Monitor.
Set the number at the bottom right to 115200. If you miss this, the text becomes garbage.
Press the EN button on the ESP32 board once. New messages should appear.

TFT_eSPI Setup

Parts 21-22 use a 2.4-inch TFT. For that, edit User_Setup.h in the TFT_eSPI library.

cpp

#define ILI9341_DRIVER
#define TFT_CS   15
#define TFT_DC   2
#define TFT_RST  -1
#define TFT_MOSI 23
#define TFT_SCLK 18
#define TFT_BL   4
#define SPI_FREQUENCY 40000000

Save the file and restart Arduino IDE.

Check Installation

Can you see ESP32 Dev Module under Tools → Board?
Can you see the ESP32 port under Tools → Port?
Try File → Examples → 01.Basics → Blink → upload. If the LED blinks, it worked.

Validate the board before adding sensors

Upload a blank sketch before connecting displays, relays, or sensors. If the bare board uploads and prints logs correctly, later failures can be investigated as wiring, power, or library problems rather than IDE setup problems.

Save project-specific settings

Record Board, Port, Upload Speed, Flash Size, and Partition Scheme. These settings become important once OTA, file storage, or multiple board variants enter the project.

Match the board family

ESP32, ESP32-C3, ESP32-S3, and ESP32-CAM are not interchangeable in Arduino IDE. The wrong selection can compile but fail to upload or behave strangely at runtime.

Upload troubleshooting order

Confirm the port appears only after plugging in the board.
Lower upload speed if flashing is unstable.
Use the BOOT button when the board cannot enter flashing mode.
Disconnect external sensors and loads during upload testing.