No
No
N/A
WiFiduinoV2
ESP32-C3 board with Arduino-like form factor - ideal for transitioning from AVR to RISC-V-based Wi-Fi projects.
68.6 × 53.4 mm
ESP32-C3
RISC-V MCU
160MHz
clock
4MB
flash
400KB
SRAM
-
GPIO
BLE 5.0+ WiFi
radio
Pinout
16 pins · 2.54 mm pitch| Pin | GPIO | Labels | Status | Capabilities | Notes |
|---|---|---|---|---|---|
| 1 | 0 | GPIO0 | adc · pwm · spi · i2c · uart | ||
| 2 | 1 | GPIO1 | adc · pwm · spi · i2c · uart | ||
| 3 | 2 | GPIO2 | adc · pwm · spi · i2c · uart | ||
| 4 | 3 | GPIO3 | adc · pwm · spi · i2c · uart | ||
| 5 | 4 | GPIO4 | adc · pwm · spi · i2c · uart | ||
| 6 | 5 | GPIO5 | adc · pwm · spi · i2c · uart | ||
| 7 | 6 | GPIO6 | pwm · spi · i2c · uart | ||
| 8 | 7 | GPIO7 | pwm · spi · i2c · uart | ||
| 9 | 8 | GPIO8 | pwm · spi · i2c · uart | ||
| 10 | 9 | GPIO9 | pwm · spi · i2c · uart | ||
| 11 | 10 | GPIO10 | pwm · spi · i2c · uart | ||
| 12 | 11 | GPIO11 | pwm · spi · i2c · uart | Requires eFuse burn (VDD_SPI) to use as a GPIO | |
| 13 | 18 | GPIO18 | pwm · spi · i2c · uart | ||
| 14 | 19 | GPIO19 | pwm · spi · i2c · uart | ||
| 15 | 20 | GPIO20 | pwm · spi · i2c · uart | ||
| 16 | 21 | GPIO21 | pwm · spi · i2c · uart |
Start with these
4 pins with no boot or system involvementGPIO0GPIO1GPIO3GPIO10
Freely assignable - no strapping, flash, USB or JTAG duties. Ideal first picks for buttons, sensors and LEDs.
Fine - with a little care
sampled at boot or shared with debug/serial| Pin | Label | What to know | Role |
|---|---|---|---|
| GPIO2 | GPIO2 | Must be held high during boot (if low on reset, normal flash boot may fail) | Strapping |
| GPIO4 | MTMS | Used during boot; JTAG TMS for debugging; acts as Quad-SPI flash IO (hold data line) in internal-flash variants | JTAG |
| GPIO5 | MTDI | Used during boot; JTAG TDI for debugging; acts as Quad-SPI flash IO (write-protect data line) in internal-flash variants | JTAG |
| GPIO6 | MTCK | Used during boot; JTAG TCK for debugging; provides flash clock in internal-flash variants | JTAG |
| GPIO7 | MTDO | Used during boot; JTAG TDO for debugging; acts as Quad-SPI flash IO (data line) in internal-flash variants | JTAG |
| GPIO8 | GPIO8 | Must be held high during reset (if low, UART flashing/boot may not work) | Strapping |
| GPIO9 | GPIO9 | Controls boot mode on reset (HIGH for normal flash boot, LOW enters serial download mode) | Strapping |
| GPIO20 | U0RXD | Used as UART0 receive (console/bootloader); repurposing may disable serial programming and debug logs | UART |
| GPIO21 | U0TXD | Used as UART0 transmit (console/bootloader); repurposing may disable serial console output and printing | UART |
Only if you know the tricks
wired to flash or USB - expect a fight| Pin | Label | What to know | Role |
|---|---|---|---|
| GPIO11 | VDD_SPI | By default powers the SPI flash; only configurable as GPIO if the flash is powered externally (not recommended otherwise) | Flash |
| GPIO18 | USB_D- | By default connected to on-chip USB Serial/JTAG controller; to use as GPIO it must be reconfigured from its USB function | USB |
| GPIO19 | USB_D+ | By default connected to on-chip USB Serial/JTAG controller; not available for GPIO use unless USB functionality is disabled or remapped | USB |
These are recommendations, not hard rules - with the right pull-ups, timing and boot-state awareness most pins can be made to work. When in doubt, start green.
Pinout notes The WiFiduinoV2 pinout brings out 16 pins at a 2.54 mm pitch - 0 usable GPIO. 9 of the exposed pins carry boot-time or system duties on the ESP32-C3 ( GPIO2 ,…
The WiFiduinoV2 pinout brings out 16 pins at a 2.54 mm pitch - 0 usable GPIO.
9 of the exposed pins carry boot-time or system duties on the ESP32-C3 (GPIO2, GPIO4, GPIO5 and 6 more) - check the guidance above before wiring anything to them. GPIO0, GPIO1, GPIO3 and GPIO10 are free of any such role - the safest first picks.
Getting started
flash your first firmware in ~2 minutes1
Connect over USB
Serial chip: CH340C. Not detected? Hold BOOT while plugging in.
2
Flash with your tool
Arduino IDE, PlatformIO, ESPHome or esptool - copy the settings on the right.
3
Verify it runs
The blink example uses GPIO8 - swap for your board's LED pin if different.
Board: Wifiduinov2
Flash Size: 4MB · QIO
Upload Speed: 921600
// blink
pinMode(8, OUTPUT);
digitalWrite(8, LOW); // on (often inverted)[env:wifiduino32c3]
platform = espressif32
board = esp32-c3-devkitm-1
framework = arduino
monitor_speed = 115200
upload_speed = 921600esp32:
board: esp32-c3-devkitm-1
variant: wifiduinov2
framework:
type: esp-idf
# blink - GPIO8
output:
- platform: gpio
pin: 8
id: led_out
light:
- platform: binary
name: "LED"
output: led_outesptool.py --chip esp32c3 --port /dev/ttyACM0 \
write_flash 0x0 firmware.binBuild details: sketch space 1310720 B · data 327680 B · QIO
Specifications
ESP32-C3 · 68.6 × 53.4 mmCompute
MCU
ESP32-C3 · RISC-V
Clock
160 MHz
SRAM · Flash
400 KB · 4MB
Radio
Wi-Fi
802.11 b/g/n
Bluetooth
5.0 LE
Antenna
PCB
I/O
GPIO · ADC
- · Two 12-bit, 6 Channels
UART · I²C · SPI
2 · 1 · 3
PWM
6 channels
Power
USB
USB-C
Serial
CH340C
Boot address
0x0
Flashing
Upload · OTA
esptool_py · esp_ota
Flash · Boot mode
QIO · QIO
Sketch · Data
1.25 MB · 320 KB
68.6 × 53.4 mm · pin pitch 2.54 mm
The WiFiduinoV2 uses esptool_py for firmware uploads, esp_ota for over-the-air (OTA) updates. Flash mode is QIO with QIO boot mode. The maximum sketch size is 1.25 MB with 320 KB available for data.
About this board
Inside sits the ESP32-C3 - a single-core RISC-V and the budget low-power pick.
Around the module: status LEDs (Power, User, TX, RX) and Reset/Boot buttons.
Resources
Similar boards
