Hi guys
Sorry for long absence. In meantime I had some luck with interesting documents found over the internet:
1)service manual of very similar camera:
http://wenku.baidu.com/view/b37abd4ffe4733687e21aa60.html2)analyze of ASCII strings from new GoPro firmware:
http://chdk.setepontos.com/index.php?topic=5890.0Finnaly, please find below full pinout of herobus connector. Numbering is based on iPod plug as follows:

1
GND 2
R video out - component Pb/Cb or composite
3
G video out - component Y
4
B video out - component Pr/Cr
5
USB +5V USB power
6
USB +5V USB power
7
USB DP-B USB data line D+
8
USB DM-B USB data line D-
9
GND 10
HPR audio out right channel
11
HPL audio out left channel
12
PWR/MODE power/mode button
13
V3.6 ?
14
IN1R audio in right channel
15
IN1L audio in left channel
16
IR IN input IR receiver
17
TRIG ?
18
GND 19
ID1 digital input
20
ID2 digital input
21
ID3 digital input
22
ID4 digital input
23
ADAPTER output - power for ext. adapter?
24
ADAPTER output - power for ext. adapter?
25
WBAT+ input - ext. power for camera?
26
WBAT+ input - ext. power for camera?
27
GND 28
DATA interface I2C
29
CLK interface I2C
30
GNDYou probably noticed some question marks - those are FUNCTIONS of the pins I'm not sure of, but names and connections to the circuit are correct.
Some description:
-
video out - in order to get composite (standard quality) video out of the bus, pins 20 (
ID2) and 21 (
ID3) must go low (can be shorted to GND). Camera will switch to "TEL" mode and on pin 2 (
R) you will find what we were looking for. In order to get HD quality (componnent), just pull only pin 20 (
ID2) down. Be aware, those outputs need 75ohm termination - just simply solder 75ohm resistors between each output and the GND;
-
USB - power pins are doubled to maintain more current during charging. Data pins in turn, I been not able to make any connection by this port (tried all combinations of ID1-4 inputs without luck);
-
HPR/HPL - audio out, operational when video switched to herobus. Unfortunately found voice only on one channel - HPR so far. Maybe by using IN1R/IN1L, stereo sound can be recorded and played - to be investigated (Xtreemtec is on the case I believe - go ahead and let us know);
-
PWR/MODE - this pin has straight connection to the front button (hooray GoPro!). Basically it acts in the same way as this button, by pulling it down (to the GND as the button does) we can turn camera on/off, change mode etc. With new software and "One Button Mode", this can be used to take snapshots, start/stop recording and all source of things (I'm sure Janmartin will enjoy of that function);
-
V3.6 - and this is mistery still. On that pin there is steady +2,5VDC and I have no idea what this pin can be for so far;
-
IR IN - I've tried a lot of remote controllers with remote receiver connected to this pin but without luck. Looking at similar devices, such as Kodak Zi6, Zi8:
http://code.google.com/p/openkodak/updates/list, based on almost same components and comparing those firmwares and GoPro firmware I came to the conclusion that IR control is not implemented yet in our device.
-
TRIG - and here is the devil - since the beginning I thought this is external shutter or something similar. Recent findings revealed that this is digital output. It does nothing in video mode, but goes down as soon as first photo is taken (in all photo modes) and stays down untill mode is changed back to video or camera is turned off/on. A bit strange function, for me more usefull could be short pulse down after each picture or something similar - anyway if somebody have idea how to use it please comment (please find, I'm still using old firmware, maybe new firmware changed that behaviour - once again comments welcome);
-
ID1-4 - so far, only input 2 and 3 made some reaction of camera (video output). Function of 1 and 4 unknown;
-
ADAPTER - looks like this is power output to feed external adapters (such as LCD). Voltage on those pins (doubled for more current) follows battery voltage during usage and is turned on/off toogether with camera by (most probably) some transistor key;
-
WBAT+ - this is the best candidate for external battery connection (doubled also for more power capability). There is ~0VDC during normal usage, but ~ +4,3VDC when USB power is connected (some voltage drop on diode? 5V-0,6(0,7)V=4,3V) - to be verified;
-
DATA,CLK - forget about my previous findings. This is I2C interface. During starting, you can capture configuration data for both audio codec and video sensor.
First (audio codec) is TLV320AIC3101 from Texas Instruments. It's I2C adreses are: 0x30[hex] for write and 0x31[hex] for read the registers.
Second (video sensor) is MT9P401 from MICRON. It's I2C adresses are: 0xBA[hex] for write and 0xBB[hex] for read the registers.
Ambarella is a master on this bus. I'm still working on that and trying to capture data for all modes.
For those, who are interested, some datasheets:
TLV320AIC3101:
http://focus.ti.com/docs/prod/folders/print/tlv320aic3101.html?lpos=Middle_Container&lid=Alternative_DevicesMT9P401 (datasheet on 6th page):
http://www.iwimage.com/download.asp?BigClassName=&SmallClassName=SGM5018:
http://www.datasheetarchive.com/SGM5018-datasheet.html