It’s time to forget about Arduino Pro Mini and move on to something 32-bit. Wemos S2 Mini ESP32 Development Board with a price of 1.00 EUR looks promising.

And let’s see if MicroPython is usable for prototyping.

ESP32-S2 Mini


  • ESP32-S2FN4R2 (Datasheet) WiFi SoC, Xtensa® single-core 32-bit LX7 microprocessor, up to 240 MHz
  • Integrated 802.11 b/g/n WiFi 2.4 GHz Transceiver, up to 150 Mbps
  • Integrated RISC-V ULP Coprocessor
  • Integrated Temperature Sensor (-20 °C to 110 °C)
  • Operating Voltage: 3.0 to 3.6 V
    • WiFi: 310 mA (peak)
    • Modem-sleep: 12-19 mA
    • Light-Sleep: 450 µA
    • Deep-Sleep: 20-190 µA
  • 320 KB SRAM
  • 4 MB Flash (embedded)
  • 2 MB PSRAM (embedded)
  • 16 KB SRAM in RTC (accessable by main CPU, 8 KB accessable by ULP coprocessor)
  • 4 Kbit eFuse (1792 bits reserved for user data)
  • 2 13-bit SAR ADCs, up to 20 channels (2 channels not available on ADC2 due to USB D+/D-) work best for voltages below 2.45V
    • 2x 8-bit DAC (second DAC FIX)
    • 14x touch sensing IOs
    • 4x SPI (2 usable due to embedded flash & PSRAM)
    • 1x I2S
    • 2x I2C
    • 2x UART
    • 1x DVP 8/16 camera interface, implemented using the hardware resources of I2S
    • 1x LCD interface (8-bit serial RGB/8080/6800), implemented using the hardware resources of SPI2
    • 1x LCD interface (8/16/24-bit parallel), implemented using the hardware resources of I2S
    • 1x TWAI® controller compatible with ISO 11898-1 (CAN Specification 2.0)
    • 8x PWM controller
    • USB OTG 1.1 controller and PHY, with host and device support
    • Cryptographic Hardware Accelerators: AES, ECB/CBC/OFB/CFB/CTR, GCM, SHA, RSA, ECC (Digital Signature)
  • USB-C connector, for built-in ROM USB bootloader, serial port debugging, and USB device mode
  • 3.3 V regulator ME6211C33
    • Input Voltage 4.7V - 6.5V (Datasheet)
    • Maximum Output Current: 500 mA (VIN=4.3 V, VOUT=3.3 V)
    • Dropout Voltage: 100 mV@ IOUT=100 mA
    • Operating Voltage Range: 2V~6.0V
    • Low Power Consumption: 40 µA (typ.)
    • Standby Current: 0.1 µA (typ.)
  • 27 GPIO pins, plus EN, VBUS, 3V3, GND, GND
    • 16 pins (outer) compatible with WEMOS/LOLIN D1 mini shields
    • EN RESET button
    • GPIO0 BOOT button
    • GPIO15 LED (blue status LED)
  • Compatible with CircuitPython, MicroPython (default firmware), Arduino and ESP-IDF

Korisni linkovi

  1. Manufacturer Specifications
  2. Factory MicroPython firmware
  3. Schematics
  4. Dimensions

Device firmware upgrade (DFU) mode

  1. Hold button 0.
  2. Short-press button RST.
  3. Release button 0.

Instalacija Micropython-a

Program your board using the esptool

# for the first time then you should erase the entire flash --chip esp32s2 --port /dev/ttyS0 erase_flash --chip esp32s2 --port /dev/ttyS0 write_flash -z 0x1000 board-20210902-v1.17.bin

for Windows replace /dev/ttyS0 with eg. COM9