# GPIO

## GPIO MISC Header (CN21)

The 40-pin GPIO header exposes GPIO, I2C, GSPI, I2S, PWM, and UART signals for
interfacing with low-level robotics hardware.

| Pin | Signal | Pin | Signal |
| :-- | :-- | :-- | :-- |
| 1 | +3V3 | 2 | +3V3 |
| 3 | GPIO2_SDA1 | 4 | +3V3 |
| 5 | GPIO3_SCL1 | 6 | GND |
| 7 | TP47 | 8 | GPIO14_TXD0 |
| 9 | +3V3 | 10 | GPIO15_RXD0 |
| 11 | GPIO17_3V3 | 12 | GPIO6_I2S1_SCLK |
| 13 | GPIO22_PWM2_3V3 | 14 | GND |
| 15 | TP42 | 16 | GPIO23_PWM3_3V3 |
| 17 | +3V3 | 18 | GPIO24_PWM4_3V3 |
| 19 | GPIO10_GSPI_MOSI | 20 | GND |
| 21 | GPIO9_GSPI_MISO | 22 | GPIO1_3V3 |
| 23 | GPIO11_GSPI_CLK | 24 | GPIO8_GSPI_CS0# |
| 25 | GND | 26 | GPIO7_3V3 |
| 27 | I2C_ID0 | 28 | I2C_ID1 |
| 29 | TP43 | 30 | GND |
| 31 | GPIO18_3V3 | 32 | GPIO12_CM_3V3 |
| 33 | GPIO13_3V3 | 34 | GND |
| 35 | GPIO19_I2S1_SFRM | 36 | GPIO16_3V3 |
| 37 | GPIO0_3V3 | 38 | GPIO20_I2S1_TXD |
| 39 | GND | 40 | GPIO21_I2S1_RXD |