for a device to be a true dual mode client/host it would need to be able to turn off the power when in client mode and back on when in host mode. then you run the risk of plugging in as a client when in host mode and sending voltage to your pc usb port and likely blowing something up along the way.
the safe way would be to have a special connector and a different cable for host and client and have the pins wired different so power can't get send when using the client cable, but now you got a special cable and no one really wants that.
That's how iRiver did it on their H3xx mp3 jukeboxes. Losing that host cable adapter must be a nightmare.
The USB chipset in the 770 has no internal power at all. So to regardless of whether you are in host or client mode, you have to provide power into the 770.
The easy way I did was to take a 4 port powered hub and steal power from one of the output ports and feed it back into the 770 in host mode. Very easy. I've got a page on the maemo wiki howto but no schematic yet.
You've not made it clear it the connection must be wired, or whether a wireless link to the lan would be accecptable. Is there a particular reason for using a wired connection?
Yes. In my work I have to test lans networks (pings, nmaps, tcpdump, etc ..). Now I go with my laptop to do this tests. If I could plug an ethernet port to my nokia 770 I could do this tests with nokia.
I had a quick nosey at portable stuff - did a quick google for usb battery-powered hubs. I found the [ CP-H420MP ] by Cyberpower. 4xAAA batteries. Another quick google puts it at [ about $20 ][ from Amazon.com ] . While I imagine you'd still have to solder the 5V rail to the input 5V rail, you've got batteries built in and won't have to make your own one a la [ hackaday.com ].
I think, either way, you'll have to do a little soldering. Perhaps you can persuade someone at your local Radio Shack to do it. I know Maplin stores in the UK generally have little guys with soldering irons. Bat your eyelids & they'll probably do it for nothing! Assuming of course you haven't access to an iron yourself...
There's an easy choice... I thought I invented the idea but I found older web pages with similar instructions. Basically if you are willing to give up one of the output ports on your hub you can just make a simple 3 headed cable that steals 5V from one of the outputs and feeds it to the 770 and the hub input.
...make a simple 3 headed cable that steals 5V from one of the outputs and feeds it to the 770 and the hub input.
You can get some great 90-degree USB plugs from [ Farnell ] and presumably other such places (maplin / radio shack / etc.) whuch might make the cable solution a little more compact & I guess you can simply do this with leccy tape (& heat shrink if you're feeling tidy). If you're soldering though, whipping upen the hub and putting a small wire on would surely be just as easy, plus you don't lose an O/P port.
What can I say, I'm a neat freak!
Alex.
Edit: Sorry David, re-reading it, my post sounds a little like one-upmanship, not meant to be!
Nah, it's just a function of philosophy I guess. Your solution is "neater" but it modifies a hub permanently. You can only use that hub with the 770 at that point and have to carry the hub with you.
My solution is messier but the hub can still be used with standard USB hosts. And my cable can be carried with you and used with any powered hub anywhere with no modifications.
And my goal when I can find the connector is to make it a 4 headed cable and add a 770 charger head to the mix. Then you basically have a "cradle cable" to go.
Yes. In my work I have to test lans networks (pings, nmaps, tcpdump, etc ..). Now I go with my laptop to do this tests. If I could plug an ethernet port to my nokia 770 I could do this tests with nokia.
I guess the point is this: There is no solution I am aware of that would let you add a standard wired ethernet connection without some kind of external powerpack. Even if you got a USB based NIC, it would still require power because the 770 does not supply USB host power.
So since your only choice involves external power anyway, why not buy a simple wifi access point? plug the wifi access point into your network and then access the system with your 770.
Or you could probably do the same thing with a bluetooth point as well.
for testing ethernet you could simplify the battery powered injector by using a 5v power brick and just have a usb cable with a power plug on it. Since you want wired access, there's likely to be a A/C plug nearby.
but yeah, either way you are going to have to MAKE something.
