3.3v DC Power Vcc	PS	+3.3V	OUT	1	2	OUT	+5V	PS	5v DC Power
Relay 1 (Big Alarm)	I2C SDA	GPIO2	OUT	3	4	OUT	+5V	PS	5v DC Power
Relay 2 (Garage Left Light Switch)	I2C SCL	GPIO3	OUT	5	6	OUT	GND	PS	Ground
Garage: 21.0C (69.8F) , 45.0%	PCM GClk	GPIO4	IN	7	8	OUT	GPIO14	UART Txd	Serial Out
Ground	PS	GND	OUT	9	10	IN	GPIO15	UART Rxd	Serial In
Relay 3 (Garage Right Light Switch)	Gen	GPIO17	OUT	11	12	OUT	GPIO18	PCM Clk	Relay 4 (DTH11 Switch)
Not Used	Gen	GPIO27	OUT	13	14	OUT	GND	PS	Ground
Not Used	Gen	GPIO22	IN	15	16	IN	GPIO23	Gen	Not Used
3.3v DC Power Vcc	PS	+3.3V	OUT	17	18	IN	GPIO24	Gen	Not Used
Not Used	SPI MOSI	GPIO10	IN	19	20	OUT	GND	PS	Ground
Not Used	SPI MISO	GPIO9	OUT	21	22	OUT	GPIO25	Gen	Not Used
Not Used	SPI SClk	GPIO11	OUT	23	24	IN	GPIO8	SPI CE0	Not Used
Ground	PS	GND	OUT	25	26	IN	GPIO7	SPI CE1	Not Used
Not Used	EEPROM I2C	ID SD	OUT	27	28	OUT	ID SC	EEPROM I2C	Not Used
Not Used	GPclk1 *	GPIO5	OUT	29	30	OUT	GND	PS	Ground
Not Used	GPClk2 *	GPIO6	OUT	31	32	IN	GPIO12	PWM0 *	Not Used
Not Used	PWM1 *	GPIO13	IN	33	34	OUT	GND	PS	Ground
Not Used	PCM FS *	GPIO19	IN	35	36	IN	GPIO16	Gen *	Not Used
Not Used	Gen *	GPIO26	IN	37	38	IN	GPIO20	PCM Din*	Not Used
Ground	PS	GND	IN	39	40	IN	GPIO21	PCM Dout*	Garage Hazardous Gas Detector

Pi2b GPIO (105) Pi2u GPIO (108) IoT Pi3b GPIO (106) Pi3g GPIO (107)

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