Herobus pinout of GoPro Hero 3+ Black

GoPro-HerobusPinout.md

pin	I/O	label	description	remark
1	-	GND	ground
2	I/O	I2CSCL	I²C clock	(pulled up by camera)
3	I/O	I2CSDA	I²C data	(pulled up by camera)
4	-	GND	ground
5	I	BATTIN	battery input
6	I	BATTIN	battery input
7	O	3V8OUT	unregulated power out 3.8V	0V when camera is off.
8	O	3V8STBY	unregulated power out 3.8V	always keep 3.8V unless battery is out.
9	I	BPRDY	bacpac ready	set low I²C EEPROM to be read by camera. (pulled up by camera)
10	I	VSYNC	3D genlock vertical sync	[LCD touch bacpac only: pulled up. set low to sleep LCD touch bacpac]
11	-	PIN11		[LCD touch bacpac only: low on audio ready]
12	-	PIN12		[LCD touch bacpac only: high on video ready]
13	-	PIN13
14	I	TRIG	3D sync trigger
15	I	I2CINT	I²C interrupt	read request from slave. (pulled up by camera)
16	I	AUDIOIN_L	left mic in	impedance 2.2k, reserved power bias 3.3V, unbalanced
17	I	AUDIOIN_R	right mic in	impedance 2.2k, reserved power bias 3.3V, unbalanced
18	-	PIN18	[LCD touch bacpac only: playback button]	(pulled up by camera)
19	I	PWRBTN	power/mode button	(pulled up by camera)
20	I	HSYNC	3D genlock horizontal sync	[LCD touch bacpac only: left audio out]
21	-	PIN21		[LCD touch bacpac only: right audio out]
22	-	GND	ground
23	I/O	USB_D−	USB D−
24	I/O	USB_D+	USB D+
25	-	USB_VBUS	USB VBUS	charging camera battery through this pin is not possible.
26	-	USB_VBUS	USB VBUS	charging camera battery through this pin is not possible.
27	-	PIN27
28	O	HBUSRDY	high on Herobus ready
29	O	VIDEO	composite video out
30	-	GND	ground