Raspberry PI - GPIO pin layout.
| 1 | 3V3 (Power) |
| 2 | 5V (Power) |
| 3 | GPIO2 (SDA1 I2C) |
| 4 | 5V (Power) |
| 5 | GPIO3 (SCL1 I2C) |
| 6 | Ground |
| 7 | GPIO4 |
| 8 | GPIO14 (UARTD_TXD) |
| 9 | Ground |
| 10 | GPIO15 (UARTD_RXD) |
| 11 | GPIO17 |
| 12 | GPIO18 (PCM_CLK) |
| 13 | GPIO27 |
| 14 | Ground |
| 15 | GPIO22 |
| 16 | GPIO23 |
| 17 | 3V3 (Power) |
| 18 | GPIO24 |
| 19 | GPIO10 (SPI0_MOSI) |
| 20 | Ground |
| 21 | GPIO9 (SPI0_MOSO) |
| 22 | GPIO25 |
| 23 | GPIO11 (SPI0_SCLK) |
| 24 | GPIO8 (SPI0_CE0_N) |
| 25 | Ground |
| 26 | GPIO7 (SPI0_CE1_N) |
| 27 | ID_SD (I2C ID EEPROM) |
| 28 | ID_SC (I2C ID EEPROM) |
| 29 | GPIO5 |
| 30 | Ground |
| 31 | GPIO6 |
| 32 | GPIO |
| 33 | GPIO |
| 34 | Ground |
| 35 | GPIO19 |
| 36 | GPIO16 |
| 37 | GPIO26 |
| 38 | GPIO20 |
| 39 | Ground |
| 40 | GPIO21 |