ESP32-H2 Super Mini Development Board as the basis for a battery-powered LoRa transmitter project

This repository accompanies a large project centered around the small ESP32-H2 Super Mini development board. It consists of several sub-projects that deal with the topics SHT41 sensor, MAX17043 battery measuring device, LoRa module, e-paper display and onboard LEDs. The end result is a LoRa transmitter that can transmit data over long distances.

Thank you for your patience-the project is now complete.

These individual tutorials are supported by a comprehensive resource where all programs and libraries are stored together. I have also saved supplementary materials such as pinouts and board schematics here. The following information is available (or will be provided soon):

• Overview tutorial "ESP32-H2 Super Mini-Small form factor, big impact (LoRa, ePaper, environment sensor, and battery powered and monitored)"
• "Use the onboard LEDs on an ESP32-H2 Super Mini Development Board": https://medium.com/@androidcrypto/use-the-onboard-leds-on-an-esp32-h2-super-mini-development-board-66a21218b809
• "Use an SSD1306 OLED display with an ESP32-H2 Super Mini Development Board": https://medium.com/@androidcrypto/use-an-ssd1306-oled-display-with-an-esp32-h2-super-mini-development-board-f97dae3a8144
• "Use an SHT41 Environment Sensor with an ESP32-H2 Super Mini Development Board and get indoor temperature and humidity": https://medium.com/@androidcrypto/use-an-sht41-environment-sensor-with-an-esp32-h2-super-mini-development-board-and-get-indoor-4404c4ffa57f
• "Use a MAX17043 battery voltage meter with an ESP32-H2 Super Mini Development Board and get the battery voltage of your lithium battery and its remaining capacity" https://medium.com/@androidcrypto/use-a-max17043-battery-voltage-meter-with-an-esp32-h2-super-mini-development-board-and-get-the-be9db05756cd
• "Commissioning of a 1.54-inch e-paper display from WeAct to an ESP32-H2 Super Mini Development Board": https://medium.com/@androidcrypto/commissioning-of-a-1-54-inch-e-paper-display-from-weact-to-an-esp32-h2-super-mini-development-board-c340cdc9a507
• "Use a UART-interfaced LoRa module with an ESP32-H2 Super Mini Development Board and transmit and receive LoRa packets": https://medium.com/@androidcrypto/use-a-uart-interfaced-lora-module-with-an-esp32-h2-super-mini-development-board-and-transmit-and-282cbb74fe76
• "Use the Deep Sleep mode to reduce power consumption on an ESP32-H2 Super Mini Development Board": https://medium.com/@androidcrypto/use-the-deep-sleep-mode-to-reduce-power-consumption-on-an-esp32-h2-super-mini-development-board-c37c6c85b460
• "Run current measurements of the individual modules connected to an ESP32-H2 Super Mini Development Board": https://medium.com/@androidcrypto/current-measurements-of-the-individual-modules-of-an-esp32-h2-project-290d676816fa
• "Build an external circuit to de-energize parts of our setup connected to an ESP32-H2 Super Mini Development Board": https://medium.com/@androidcrypto/lets-build-an-external-circuit-to-de-energize-parts-of-our-esp32-h2-setup-during-deep-sleep-time-a1ec6de43cf7
• "ESP32-H2 Super Mini LoRa UART Module Receiver": https://medium.com/@androidcrypto/esp32-h2-super-mini-lora-uart-module-receiver-00ef3fd467a2
• the final project: "ESP32-H2 Super Mini with environment sensor, battery voltage reading, e-paper display, and LoRa transmission module (the complete project)": https://medium.com/@androidcrypto/esp32-h2-super-mini-with-environment-sensor-battery-voltage-reading-e-paper-display-and-lora-80678ed47842

The additional material is located in the subfolder "Material":

• the pinout of the ESP32-H2 Super Mini Development board
• the schematic of the ESP32-H2 Super Mini Development board
• the datasheet of the IRLB3034 N-MOSFET

The code of each sketch is in sepate folders. All libraries used within the sketches should get installed with the Arduino Library Manager, but in case of network or other problems, I'm including them in the subfolder "Libraries".

Sketches for the tutorials

• Find the "Onboard LEDs" sketch in Esp32_H2_SM_OnboardLeds_v02 folder
• Find the "SSD1306 OLED" sketch in Esp32_H2_SM_SSD1306_OLED_v02 folder
• Find the "SHT41 Sensor" sketch in Esp32_H2_SM_SHT41_Sensor_v02 folder
• Find the "SHT41 Sensor with SSD1306 OLED" sketch in Esp32_H2_SM_SHT41_SSD1306_OLED_v01 folder
• Find the "MAX17043" sketch in Esp32_H2_SM_MAX17043_v03 folder
• Find the "MAX17043 with SSD1306 OLED" sketch in Esp32_H2_SM_MAX17043_SSD1306_OLED_v03 folder
• Find the "WeAct 1.54-inch e-paper" sketch in Esp32_H2_SM_WeAct154_Epaper_v01 folder
• Find the "UART LoRa" sketch in Esp32_H2_SM_LoRa_Uart_v01 folder
• Find the "UART LoRa with SSD1306 OLED" sketch in Esp32_H2_SM_LoRa_Uart_SSD1306_OLED_v01 folder
• Find the "Deep Sleep" sketch in Esp32_H2_SM_DeepSleep_v01 folder
• Find the "Advanced Receiver" sketch in Esp32_H2_SM_LoRa_Uart_Receiver_v01 folder
• Find the "Complete Project" sketch in Esp32_H2_SM_LoRa_Transmitter_Final_v05 folder

Development Environment (Arduino)

Arduino IDE Version 2.3.6 / 2.3.7 / 2.3.8 (Windows)
arduino-esp32 boards Version 3.3.5 / 3.3.6 / 3.3.7 (https://github.com/espressif/arduino-esp32) that is based on Espressif ESP32 Version 5.5.1

Last update: February, 28 th. 2026