Arduino Pro Mini Pinout
Find the Arduino Pro Mini pinout, digital and analog pins, memory limits, and Circuitera compile/upload support. Check board-specific library compatibility.
- Processor
- ATMEGA328P
- Clock
- 16 MHz
- Physical flash
- 32768 bytes
- Application flash
- 30720 bytes
- SRAM
- 2048 bytes
- EEPROM
- 1024 bytes
- Digital pins
- 14
- Analog inputs
- 8
- PWM
- D3, D5, D6, D9, D10, D11
- Hardware UARTs
- 1
- UART pins
- D0, D1
- I2C
- A4, A5, SDA, SCL
- SPI
- D10, D11, D12, D13
- External interrupts
- D2, D3
- Logic voltage
- 5 V
- Bootloader
- ATmegaBOOT · external serial adapter
- Protocol / baud
- STK500v1 · 57600
- Compile capability
- Verified · automated compile
- Upload capability
- Untested · physical hardware
- Serial capability
- Untested · physical hardware
- Simulation
- Not supported for this profile
- Build-matched compile check
- 2026-10-25
Choose the exact board
Requires a compatible USB-to-serial adapter with matching logic voltage and DTR reset (or manual Reset). A6/A7 are analog-only. Hardware upload validation is pending.
Compile, upload, and simulation
Real AVR-GCC compilation uses eightanaloginputs and the selected clock. Upload is experimental pending physical hardware validation. Simulation is not yet supported for this board.
Memory and signals
Application flash excludes the bootloader. SRAM use reported after Verify excludes runtime stack and heap. Check the pin reference below before connecting a circuit.
Upload and validation limits
Requires a compatible USB-to-serial adapter with matching logic voltage and DTR reset (or manual Reset). A6/A7 are analog-only. Hardware upload validation is pending.
No physical upload certification recorded in these build reports. Compile capability, simulated protocol tests and physical upload are separate claims.
Toolchain: avr-gcc-wasm@0.2.0. Last matching compile evidence: 2026-10-25. Build: e0f6d304cce4ae0a0989a9b1300cbc1a21a595e5e3e7f57ed0ab3468ecf7940b.
Choose the exact variant
The specifications above use Arduino Pro Mini — 5 V · 16 MHz. Check the voltage, clock and bootloader for your physical board before connecting an adapter or compiling.
| Profile | Clock | Logic voltage | Bootloader | Upload baud |
|---|---|---|---|---|
| Arduino Pro Mini — 5 V · 16 MHz | 16 MHz | 5 V | ATmegaBOOT · external serial adapter | 57600 |
| Arduino Pro Mini — 3.3 V · 8 MHz | 8 MHz | 3.3 V | ATmegaBOOT · external serial adapter | 57600 |
Arduino Pro Mini pinout table
Every pin and alias is present in the initial HTML. Filter by signal capability, or select a pin for its existing reference details. Disconnect power before changing wiring.
28 pin entries
Select a pin to read its capabilities.
| Pin | Capabilities | Details |
|---|---|---|
| DIGITAL · UART | RX · TTL UART; USB-to-serial adapter required | |
| DIGITAL · UART | TX · TTL UART; USB-to-serial adapter required | |
| DIGITAL · INTERRUPT | External interrupt INT0 | |
| DIGITAL · PWM · INTERRUPT | External interrupt INT1 · PWM | |
| DIGITAL | Digital input/output | |
| DIGITAL · PWM | Digital input/output · PWM with analogWrite() | |
| DIGITAL · PWM | Digital input/output · PWM with analogWrite() | |
| DIGITAL | Digital input/output | |
| DIGITAL | Digital input/output | |
| DIGITAL · PWM | Digital input/output · PWM with analogWrite() | |
| DIGITAL · PWM · SPI | SS · SPI chip select | |
| DIGITAL · PWM · SPI | MOSI · SPI data to peripherals | |
| DIGITAL · SPI | MISO · SPI data from peripherals | |
| DIGITAL · SPI | SCK · also connected to the onboard LED | |
| ANALOG · DIGITAL | 10-bit analog input (0–1023). Also digital pin 14. | |
| ANALOG · DIGITAL | 10-bit analog input (0–1023). Also digital pin 15. | |
| ANALOG · DIGITAL | 10-bit analog input (0–1023). Also digital pin 16. | |
| ANALOG · DIGITAL | 10-bit analog input (0–1023). Also digital pin 17. | |
| ANALOG · DIGITAL · I2C | 10-bit analog input (0–1023). Also digital pin 18. SDA · same signal as SDA. | |
| ANALOG · DIGITAL · I2C | 10-bit analog input (0–1023). Also digital pin 19. SCL · same signal as SCL. | |
| GROUND | Common ground reference. Join the ground of connected modules to GND. | |
| RESET | Pulling RESET low restarts the microcontroller. The reset button does the same. | |
| I2C · DIGITAL · ANALOG | I2C data. Electrically the same pin as A4, not an extra independent pin. | |
| I2C · DIGITAL · ANALOG | I2C clock. Electrically the same pin as A5, not an extra independent pin. | |
| ANALOG | 10-bit analog input (0–1023), analog-only. Use analogRead(). This pin cannot use digitalRead(), digitalWrite(), pinMode() or PWM. | |
| ANALOG | 10-bit analog input (0–1023), analog-only. Use analogRead(). This pin cannot use digitalRead(), digitalWrite(), pinMode() or PWM. | |
| POWER | Regulated 5 V supply / logic. Match your adapter voltage. | |
| POWER | Regulator input; check the particular Pro Mini regulator rating. |
Library compile results
Actual source/hash-matched results for this exact profile. A passed compile does not prove a real peripheral, motor or wiring works.
| Library | Pinned version | Result | Flash / static RAM | Test date |
|---|---|---|---|---|
| HID | 1.0 | UNSUPPORTED | Not recorded | 2026-10-25 |
| Keyboard | 1.0.7 | UNSUPPORTED | Not recorded | 2026-10-25 |
| Mouse | 1.0.1 | UNSUPPORTED | Not recorded | 2026-10-25 |
| Servo | 1.3.0 | PASS | 2522 / 50 bytes | 2026-10-25 |
| Wire | 1.0 | PASS | 4494 / 408 bytes | 2026-10-25 |
| SPI | 1.0 | PASS | 2728 / 192 bytes | 2026-10-25 |
| EEPROM | 2.0 | PASS | 2428 / 188 bytes | 2026-10-25 |
| SoftwareSerial | 1.0 | PASS | 3466 / 301 bytes | 2026-10-25 |
| LiquidCrystal | 1.0.7 | PASS | 2232 / 59 bytes | 2026-10-25 |
| DHT | 1.4.7 | PASS | 5610 / 219 bytes | 2026-10-25 |
| Adafruit Unified Sensor | 1.1.15 | PASS | 9230 / 302 bytes | 2026-10-25 |
| Adafruit GFX | 1.12.6 | PASS | 10956 / 533 bytes | 2026-10-25 |
| Adafruit SSD1306 | 2.5.17 | PASS | 13868 / 399 bytes | 2026-10-25 |
| Adafruit BusIO | 1.17.4 | PASS | 7144 / 438 bytes | 2026-10-25 |
| Adafruit NeoPixel | 1.15.5 | PASS | 3270 / 41 bytes | 2026-10-25 |
| NewPing | 1.9.7 | PASS | 3304 / 209 bytes | 2026-10-25 |
| IRremote | 4.7.1 | PASS | 12100 / 491 bytes | 2026-10-25 |
| Keypad | 3.1.1 | PASS | 3922 / 327 bytes | 2026-10-25 |
| AccelStepper | 1.64 | PASS | 6118 / 119 bytes | 2026-10-25 |
| LiquidCrystal_I2C | 1.1.2 | PASS | 4006 / 275 bytes | 2026-10-25 |
Projects and next steps
The public tutorials are validated on Uno. Their concepts can help with this board, but wiring, pin maps, libraries and the exact profile must be reviewed and verified separately; they are not claimed as tested projects on this board.