Serial like interaction with external devices through dock connector?(gigabeat)

[jchord]

First of all Rockbox is AMAZING!
Now that I have that out of the way...

I was wondering if it is possible that you could make a serial like connection to a device through the gigabeat's bock connector. Cause that would open up a whole lot of hacks that it would be possible to do. I know there is the Custom dock project but that page does not say if it is possible to do something like this. I'm not very knowledgeable on how any of the hardware works. (I'm more of a software guy) However if this where possible it would be cool cause I would love to learn all this stuff and that would enable to make little projects that I could control through the gigabeat or add use to add functions to the gigabeat.

Thanks,
John Berube