Unexpected Maker ProS3

Board
by Unexpected Makerum-pros3≈ medium (~$15–50)

Also known as: PROS3

Verify my boardCompareEdit on GitHub
Flash this board — 1 firmware option · Unverified
Unexpected Maker ProS3 pinout
Pinout

Specifications

Radiosinherited from ESP32-S3

Wi-Fi
Wi-Fi 4 · 2.4 GHz
Bluetooth LE
BLE 5
Bluetooth Classic
no
802.15.4
no

USB

Native USB
yes

Board

Form factor
pros3
Dimensions
53 × 17.8 mm
Battery connector
yes
Charging
yes

Display & extras

Extras
stemma-qt
Built onUnexpected Maker ProS3 BoardESP32-S3 SoC

Feature-loaded ESP32-S3 board: 16 MB flash, 8 MB PSRAM, LiPo header + Microblade charging, and a STEMMA QT / Qwiic port, in a compact 53 x 17.8 mm outline.

Firmware for this board

Unverified

  • ESP32 Bit PirateUnverifiedpentest
    Flash ESP32 Bit Pirateguided

    Unverified esp-atlas asserts this board↔firmware link at the shown trust tier — it does not guarantee your specific unit or the current firmware version. Flashing can erase keys/config and can brick the device. At your own risk.

Notes

  • 16 MB external flash, 8 MB external PSRAM
  • LiPo battery via header + Microblade connector on top
  • One STEMMA QT / Qwiic port
  • USB connector type not stated on the cited spec matrix (omitted)
  • io.gpio_exposed=27 QUOTED: vendor page states "27x GPIO including castellated headers"
  • io.power_out QUOTED: vendor page states "2x 700mA 3.3V LDO Regulators"; LDO2 is described as "for you to use to connect external 3V3 modules, sensors and peripherals" (EN tied to IO17, auto-shuts down in deep sleep) -- rail_v/rail_ma_max reflect this external-use LDO2, not the shared LDO1
  • io.gpio_free=22 DERIVED: CircuitPython's board pin table (unexpectedmaker_pros3/pins.c) lists 28 IO-numbered pins {0-9,12-16,17,21,34-42,43,44}; excluding GPIO17 (LDO2/NeoPixel-power enable -- onboard-dedicated despite carrying an IO17 alias; NeoPixel data GPIO18 carries no IO-alias) leaves 27 GPIO {0-9,12,13,14,15,16,21,34,35,36,37,38,39,40,41,42,43,44}, matching vendor's "27" exactly. Subtracting esp32-s3's soc.reserved_pins present in that 27-pin set (strapping {0,3}: 2; usb_flash_tied {35,36,37}: 3 -- 5 total) gives 27 - 5 = 22

Verify my board

Reads the connected chip over USB and checks it against what esp-atlas cites for Unexpected Maker ProS3 — over Web Serial, no backend, nothing leaves your browser.

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Serial monitor

Not connected.