DOIT ESPduino32
by DOIT
ESP32 dev board with Arduino Uno layout - combines Wi-Fi power with classic compatibility.

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Pinout
35 pins · 2.54 mm pitch| Pin | GPIO | Labels | Status | Capabilities | Notes |
|---|---|---|---|---|---|
| 1 | 0 | IO0 | strapping | - | |
| 2 | 1 | TX0PWM | uart | - | |
| 3 | 2 | LED_BUILTINIO2PWM | strapping | - | |
| 4 | 3 | RX0PWM | uart | - | |
| 5 | 4 | IO4PWM | strapping | - | |
| 6 | 5 | IO5PWM | strapping | - | |
| 7 | 6 | CLKPWM | strapping | - | |
| 8 | 7 | SD0PWM | strapping | - | |
| 9 | 8 | SD1PWM | strapping | - | |
| 10 | 9 | SD2PWM | strapping | - | |
| 11 | 10 | SD3PWM | strapping | - | |
| 12 | 11 | CMDPWM | strapping | - | |
| 13 | 12 | IO12PWM | strapping | - | |
| 14 | 13 | IO13PWM | strapping | - | |
| 15 | 14 | IO14PWM | strapping | - | |
| 16 | 15 | IO15PWM | strapping | - | |
| 17 | 16 | IO16PWM | strapping | - | |
| 18 | 17 | IO17PWM | strapping | - | |
| 19 | 18 | IO18PWM | safe | - | |
| 20 | 19 | IO19PWM | safe | - | |
| 21 | 21 | SDAPWM | safe | i2c | |
| 22 | 22 | SCLPWM | safe | i2c | |
| 23 | 23 | IO23PWM | safe | - | |
| 24 | 25 | IO25PWM | safe | - | |
| 25 | 26 | IO26PWM | safe | - | |
| 26 | 27 | IO27PWM | safe | - | |
| 27 | 32 | IO32PWM | safe | - | |
| 28 | 33 | IO33PWM | safe | - | |
| 29 | 35 | IO35 | strapping | - | |
| 30 | 36 | IO36 | strapping | - | |
| 31 | 39 | IO39 | strapping | - | |
| 32 | 5 | SS | strapping | spi | |
| 33 | 23 | MOSI | safe | spi | |
| 34 | 19 | MISO | safe | spi | |
| 35 | 18 | SCK | safe | spi |
Start with these
13 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
sampled at boot or shared with debug/serial| Pin | Label | What to know | Role |
|---|---|---|---|
| IO0 | GPIO0 | Must be HIGH during boot for normal startup; if held LOW on reset, forces flash programming mode. | Strapping |
| LED_BUILTIN | GPIO2 | If driven HIGH on reset (while IO0 is LOW), selects an unsupported SDIO boot mode, causing boot failure. | Strapping |
| IO4 | GPIO4 | Sampled at reset for boot config; should not be driven at boot (affects boot mode timing). | Strapping |
| IO5 | GPIO5 | Must be HIGH during boot; if pulled LOW at reset, alters SDIO slave timing and may prevent normal boot. | Strapping |
| IO12 | MTDI (GPIO12) | Keep LOW during boot (internal PD); pulling HIGH at reset selects 1.8V flash mode, causing flash brownout if 3.3V flash is used. | Strapping |
| IO13 | MTCK (GPIO13) | Used for JTAG debugging (TCK); avoid using as GPIO if JTAG is needed. | Other |
| IO14 | MTMS (GPIO14) | Used for JTAG debugging (TMS); driving it as GPIO may interfere with JTAG or produce spurious signals at boot. | Other |
| IO15 | MTDO (GPIO15) | Keep HIGH during boot (internal PU); if LOW on reset, bootloader log is silenced and boot mode may change. | Strapping |
| IO35 | GPIO35 | Cannot be used as output; only suitable for input. | Other |
| IO36 | GPIO36 (SENSOR_VP) | Cannot be used as output; only suitable for input (e.g., analog read). | Other |
| IO39 | GPIO39 (SENSOR_VN) | Cannot be used as output; only suitable for input. | Other |
| SS | GPIO5 | Must be HIGH during boot; if pulled LOW at reset, alters SDIO slave timing and may prevent normal boot. | Strapping |
Only if you know the tricks
wired to flash or USB - expect a fight| Pin | Label | What to know | Role |
|---|---|---|---|
| TX0 | U0TXD (GPIO1) | Connected to on-board USB-UART for uploading and logs; drives serial output at boot, so using as GPIO can disrupt programming or console. | USB |
| RX0 | U0RXD (GPIO3) | Used for receiving data from USB-UART (programming); also pulled HIGH at boot for console communication, so using as GPIO can disrupt uploads. | USB |
| CLK | GPIO6 (Flash SCK) | Used for internal flash/PSRAM communication; not available for general GPIO. | Flash |
| SD0 | GPIO7 (Flash SD0) | Used for internal flash/PSRAM data; not available for general GPIO. | Flash |
| SD1 | GPIO8 (Flash SD1) | Used for internal flash/PSRAM data; not available for general GPIO. | Flash |
| SD2 | GPIO9 (Flash SD2) | Used by internal flash/PSRAM; typically not exposed on modules, avoid using as GPIO. | Flash |
| SD3 | GPIO10 (Flash SD3) | Used by internal flash/PSRAM; typically not exposed on modules, avoid using as GPIO. | Flash |
| CMD | GPIO11 (Flash CMD) | Used by internal flash (chip select/command); not available for general use. | Flash |
| IO16 | GPIO16 | Connected to internal PSRAM on PSRAM-enabled modules; not usable as GPIO on those modules. | Flash |
| IO17 | GPIO17 | Connected to internal PSRAM on PSRAM-enabled modules; not usable as GPIO on those modules. | Flash |
Pinout notes All 35 pins on the DOIT ESPduino32 are usable GPIO, spaced at the standard 2.54 mm pitch. Peripheral wiring is straightforward: I²C is mapped to SDA on GPIO21…
All 35 pins on the DOIT ESPduino32 are usable GPIO, spaced at the standard 2.54 mm pitch.
Peripheral wiring is straightforward: I²C is mapped to SDA on GPIO21 and SCL on GPIO22, while the SPI bus (MOSI, MISO, SCK, SS) is broken out in full.
12 of the exposed pins carry boot-time or system duties on the ESP32 (IO0, LED_BUILTIN, IO4 and 9 more) - check the guidance above before wiring anything to them. IO18, IO19, SDA, SCL and 9 more are free of any such role - the safest first picks.
Getting started
flash your first firmware in ~2 minutesBoard: ESP32 Dev Module Flash Size: 4MB (32Mb) Flash Mode: DIO Partition Scheme: Default 4MB with spiffs (1.2MB APP / 1.5MB SPIFFS) Upload Speed: 921600
// blink the onboard LED
void setup() {
pinMode(18, OUTPUT);
}
void loop() {
digitalWrite(18, HIGH); delay(500);
digitalWrite(18, LOW); delay(500);
}[env:esp32doit-espduino]
platform = espressif32
board = esp32dev
framework = arduino
monitor_speed = 115200
upload_speed = 921600esp32dev — or type it after board =.esp32:
board: esp32dev
variant: doitESPduino32
framework:
type: esp-idf
# blink - GPIO18
output:
- platform: gpio
pin: 18
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 0x0 firmware.bin--port = your /dev/tty* (macOS/Linux) or COMx (Windows).Specifications
ESP32 · 66 × 53.3 mmAbout this board
Inside sits the ESP32 - a dual-core Xtensa with both Bluetooth Classic and BLE.
With 31 GPIO broken out, you get more pins to play with than most ESP32 boards offer.
Around the module: Reset buttons.
Resources
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