The following table describes the pins available on the Arduino board, and their purpose in the Kegboard firmware.
| Digital Pin | Description |
|---|---|
| 2 | Flowmeter A input |
| 3 | Flowmeter B input |
| 4 | Relay A output |
| 5 | Relay B output |
| 6 | unused |
| 7 | Thermo OneWire bus |
| 8 | Presence OneWire bus |
| 9 | Alarm output |
| 10 | unused |
| 11 | Buzzer output |
| 12 | Test pulse output |
| 13 | unused |