Unexpected Maker TinyS2 ESP32-S2 Development Board (TinyS2)
Unexpected Maker TinyS2 ESP32-S2

Available from:


Install method:
USB to Serial

GPIO #Component
GPIO00 User
GPIO01 WS2812 1
GPIO02 Output Hi
GPIO03 ADC Input 1
GPIO04 User
GPIO05 User
GPIO06 User
GPIO07 User
GPIO08 User
GPIO09 User
GPIO10 None
GPIO11 None
GPIO12 None
GPIO13 None
GPIO14 User
GPIO15 None
GPIO16 None
GPIO17 User
GPIO18 User
GPIO19 None
GPIO20 None
GPIO21 None
GPIO33 User
GPIO34 None
GPIO35 User
GPIO36 User
GPIO37 User
GPIO38 User
GPIO39 None
GPIO40 None
GPIO41 None
GPIO42 None
GPIO43 Serial Tx
GPIO44 Serial Rx
GPIO45 None
GPIO46 None
Configuration for ESP32-S2

A small form factor ESP32-S2 dev board.

This board uses an ESP32-S2F-N4R2 chip with 4 MB of flash and 2 MB of PSRAM.

When the board is booted into debug by holding BOOT and pressing the RESET button the USB port exposes a serial connection. This can be used to easily flash new firmware.


Flash using Tasmota Web Installer and select Tasmota ESP32-S2 option.

For esptool.py download i.e. tasmota32s2.factory.bin and run esptool.py write_flash 0x0 tasmota32s2.factory.bin

To put ESP32-S2 in flash mode GPIO0 needs to be pulled low.

Device Notes

Unexpected Maker TinyS2 Front

There are two versions of the TinyS2 with slightly different pinouts for the SPI pins.

Unexpected Maker TinyS2 P1 Pinout

Unexpected Maker TinyS2 P3 Pinout

TinyS2 Schematic


  • WS2812B Neopixel
    • On GPIO1 with power on GPIO2.
    • Provided template configures this as WS2812 with GPIO2 as Output Hi for power.
  • 1S LiPo battery management subsystem with 2-pin JST-SH connector
    • Battery voltage on GPIO3 and 5V/voltage detection on GPIO21
    • Provided template configures GPIO3 as ADC Input 1 and does not configure GPIO21.

GPIO Pin Mapping

The user pins labelled on the board are set up as User pins in the template.The pin numbers match the ESP’s internal GPIO number assignments allowing relatively easy module configuration without having to translate pin.

The only exception are the pins labeled TX and RX, which are set up as Serial TX/RX in the template.