Nanopi Fire3 - pinout

40 pin IO connector

Pin#	Name	Pin#	Name
1	SYS_3.3V	2	VDD_5V
3	I2C0_SDA	4	VDD_5V
5	I2C0_SCL	6	DGND
7	GPIO D8 / PPM	8	UART3_TXD/GPIO D21
9	DGND	10	UART3_RXD/GPIO D17
11	UART4_TX/GPIO B29	12	GPIO D1/PWM0
13	GPIO B30	14	DGND
15	GPIO B31	16	GPIO C14/PWM2
17	SYS_3.3V	18	GPIO B27
19	SPI0_MOSI/GPIO C31	20	DGND
21	SPI0_MISO/GPIO D0	22	UART4_RX/GPIO B28
23	SPI0_CLK/GPIO C29	24	SPI0_CS/GPIO C30
25	DGND	26	GPIO B26
27	I2C1_SDA	28	I2C1_SCL
29	GPIO C8	30	DGND
31	GPIO C7	32	GPIO C28
33	GPIO C13/PWM1	34	DGND
35	SPI2_MISO/GPIO C11	36	SPI2_CS/GPIO C10
37	Alive GPIO3	38	SPI2_MOSI/GPIO C12
39	DGND	40	SPI2_CLK/GPIO C9

The "Alive" port has 6 bits, only one of which (Alive-GPIO3) appears on this connector (on pin 37). Alive-GPIO0 is connected to the Pwr button. The "Alive" port stays active when the rest of the device is powered down (core power is off). This is discussed in section 13 of the user manual.

Serial Console (UART0)

Pin#	Name
1	DGND
2	VDD_5V
3	UART_TXD0
4	UART_RXD0