Adafruit Feather ESP32 V2
Updated Feather ESP32 with improved power handling and USB-C - great for portable IoT and CircuitPython use.
Adafruit Feather ESP32 V2 Pinout
24 pins · 2.54 mm pitch
| Pin | GPIO | Labels | Status | Capabilities | Notes |
|---|---|---|---|---|---|
| 1 | 0 | PIN_NEOPIXELT1 | strapping | touch | |
| 2 | 2 | NEOPIXEL_I2C_POWERT2PWM | strapping | touch | |
| 3 | 4 | A5T0PWM | strapping | adc · touch | |
| 4 | 5 | SCKPWM | strapping | spi | |
| 5 | 7 | RXPWM | strapping | uart | |
| 6 | 8 | TXPWM | strapping | uart | |
| 7 | 12 | A11T5PWM | strapping | adc · touch | |
| 8 | 13 | LED_BUILTINA12T4PWM | strapping | adc · touch | |
| 9 | 14 | A6T6PWM | strapping | adc · touch | |
| 10 | 15 | A8T3PWM | strapping | adc · touch | |
| 11 | 19 | MOSIPWM | safe | spi | |
| 12 | 20 | SCLPWM | safe | i2c | |
| 13 | 21 | MISOPWM | safe | spi | |
| 14 | 22 | SDAPWM | safe | i2c | |
| 15 | 25 | A1DAC1PWM | safe | adc · dac | |
| 16 | 26 | A0DAC2PWM | safe | adc · dac | |
| 17 | 27 | A10T7PWM | safe | adc · touch | |
| 18 | 32 | A7T9PWM | safe | adc · touch | |
| 19 | 33 | SSA9T8PWM | safe | adc · touch · spi | |
| 20 | 34 | A2 | strapping | adc | |
| 21 | 35 | A13BATT_MONITOR | strapping | adc | |
| 22 | 36 | A4 | strapping | adc | |
| 23 | 38 | BUTTON | strapping | - | |
| 24 | 39 | A3 | strapping | adc |
Start with these
9 pins with no boot or system involvementFreely assignable - no strapping, flash, USB or JTAG duties. Ideal first picks for buttons, sensors and LEDs.
Fine - with a little care
13 pins · 11 things to knowPIN_NEOPIXELGPIO0 Bootstrapping pin (enter bootloader when low); internal pull-up. Strapping
Must be HIGH during boot for normal startup; if held LOW on reset, forces flash programming mode.
NEOPIXEL_I2C_POWERGPIO2 Bootstrapping pin (must be low or floating at reset); internal pull-down. Strapping
If driven HIGH on reset (while IO0 is LOW), selects an unsupported SDIO boot mode, causing boot failure.
A5GPIO4 Bootstrapping pin; internal pull-down; also HSPIHD (flash data line) on modules with internal flash. Strapping
Sampled at reset for boot config; should not be driven at boot (affects boot mode timing).
SCKGPIO5 Bootstrapping pin; internal pull-up; VSPI CS0 (default SPI chip-select); acts as FSPIWP (flash write-protect) on internal-flash variants. Strapping
Must be HIGH during boot; if pulled LOW at reset, alters SDIO slave timing and may prevent normal boot.
A11GPIO12 Bootstrapping pin; JTAG TDI; sets flash voltage (VDD_SDIO); also HSPIQ (flash data line). Strapping
Keep LOW during boot (internal PD); pulling HIGH at reset selects 1.8V flash mode, causing flash brownout if 3.3V flash is used.
LED_BUILTINGPIO13 JTAG clock pin (TCK); also ADC2 channel 4 / Touch4 input. JTAG
Used for JTAG debugging (TCK); avoid using as GPIO if JTAG is needed.
A6GPIO14 JTAG mode select pin (TMS); also HSPI CLK and PWM-capable GPIO. JTAG
Used for JTAG debugging (TMS); driving it as GPIO may interfere with JTAG or produce spurious signals at boot.
A8GPIO15 Bootstrapping pin; JTAG TDO; controls UART0 boot log output; also HSPICS0 (secondary SPI CS). Strapping
Keep HIGH during boot (internal PU); if LOW on reset, bootloader log is silenced and boot mode may change.
A2GPIO34 Input-only GPIO (no output driver); ADC1 channel 6. Other
Cannot be used as output (no drive capability); only suitable for analog/digital input.
A13GPIO35BUTTONGPIO38A3GPIO39 Input-only GPIOs with ADC1 channels - no output driver Other
Cannot be used as output; only suitable for input.
- A13Input-only GPIO (no output driver); ADC1 channel 7.
- BUTTONInput-only GPIO (no output); ADC1 channel 2.
- A3Input-only GPIO (no output); ADC1 channel 3, Hall sensor VN.
A4GPIO36 Input-only GPIO (no output); ADC1 channel 0, Hall sensor VP. Other
Cannot be used as output; only suitable for input (e.g., analog read).
Only if you know the tricks
2 pins · 1 thing to knowRXGPIO7TXGPIO8 SPI flash data lines SD0 and SD1 Flash
Used for internal flash/PSRAM data; not available for general GPIO.
- RXConnected to SPI flash data 0 (SD0).
- TXConnected to SPI flash data 1 (SD1).
All 24 pins on the Adafruit Feather ESP32 V2 are usable GPIO, spaced at the standard 2.54 mm pitch.
Peripheral wiring is straightforward: I²C is mapped to SDA on GPIO22 and SCL on GPIO20; the SPI bus (MOSI, MISO, SCK, SS) is broken out in full; TX/RX on GPIO8 and GPIO7 cover serial logging and flashing.
Beyond plain digital I/O you get 14 ADC-capable pins for sensors and battery monitoring, 10 capacitive-touch inputs and 2 true DAC outputs.
13 of the exposed pins carry boot-time or system duties on the ESP32 (PIN_NEOPIXEL, NEOPIXEL_I2C_POWER, A5 and 10 more) - check the guidance above before wiring anything to them. MOSI, SCL, MISO, SDA and 5 more are free of any such role - the safest first picks.
Getting started
flash your first firmware in ~2 minutesBoard: ESP32 Wrover Module Flash Size: 8MB (64Mb) Flash Mode: DIO PSRAM: QSPI PSRAM Partition Scheme: 8M with spiffs (3MB APP/1.5MB SPIFFS) Upload Speed: 921600
// toggle GPIO19 - wire an LED and resistor to it
void setup() {
pinMode(19, OUTPUT);
}
void loop() {
digitalWrite(19, HIGH); delay(500);
digitalWrite(19, LOW); delay(500);
}[env:adafruit_feather_esp32_v2]
platform = espressif32
board = esp32dev
framework = arduino
monitor_speed = 115200
upload_speed = 921600
board_build.arduino.memory_type = qio_qspi
build_flags = -DBOARD_HAS_PSRAMesp32dev - or type it after board =.esp32:
board: esp32dev
variant: esp32
framework:
type: esp-idf
psram:
mode: quad
speed: 80MHz
# blink - GPIO19
output:
- platform: gpio
pin: 19
id: led_out
light:
- platform: binary
name: "LED"
output: led_outesp32dev (same ids as PlatformIO).esptool.py --chip esp32 --port /dev/ttyACM0 \
--baud 921600 write_flash 0x1000 firmware.bin--port = your /dev/tty* (macOS/Linux) or COMx (Windows).Specifications
ESP32 · 52.3 × 22.8 mm · vs other ESP32 chips →Dimensions
About this board
Inside sits the ESP32 - a dual-core Xtensa with both Bluetooth Classic and BLE.
The $19.95 price tag is typical for an ESP32 board.
Around the module: 2MB (QSPI) PSRAM, a STEMMA QT connector, battery charging via JST-PH 2.0, status LEDs (Charge, User (D13)) and Reset/User (D38) buttons.
- Battery voltage read via a resistor divider on GPIO35 (no dedicated fuel-gauge IC)
- Boards made before 19 May 2022 shipped with a CP2102N USB-serial chip instead of the CH9102F
- A separate variant (#5438) adds a u.FL connector for an external antenna
Where to buy
prices are typical street pricesResources
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