Touch i2c bus on Kobo Touch N905

I noticed that my Kobo touch N905 (not B or C) has i2c commands in one of the bin folders.

I found a copy of i2cdetect , loaded it and did
i2cdetect 0

I saw one response at hex68

So it must have an i2c bus (?)

I am into Linux on routers etc (http://www.sunspot.co.uk) and would love to use Kobo as a controller on my i2c network (good screen for full sun in the greenhouse!)
I would set up a website on the Kobo and display it in the inbuilt browser. I guess you could do cgi scripting?

Has anyone any knowledge of where the i2c connects?
(On an NSLU2 router there is also just one response from a real-time clock, but not at hex68)

I want to find the bus lines and interface them out.
What chip might use them?

Also
Has anyone seen the rs232 port on the old N905 (no B or C)?
There is nothing obvious on this old design board.

:help: