Ethernet shield and x-over cable

Hi peeps,

The geography of my house is such that it's a pita to sit within drop cable length of my router to get the Ethernet shield plugged in.

Am I right in thinking that, for testing of basic functionality, I'd be ok plugging it into my laptop with a x-over "null-hub" cable?

Thought I'd check before I pop anything...



You can use either type cable. The w5100 supports crossover.

Yeah, most Ethernet connectors, now days, automatically detect whether they need a crossover, and will cross themselves over, if it's needed.

Even if your shield doesn't have this capability, (and the poster above me says it does), your laptop almost certainly does. And, as long as EITHER end of the cable has this "Auto MDI" capability, then your physical connection is good.

Now, if you're just using a crossover cable, then you do lose a lot of other functionality. Like, there's no DHCP server on your "network". (Unless you've installed software on your laptop to do this.) So both your shield and laptop will have to use manually assigned IP addresses. (And there's no DNS server, and so forth.)

This auto-crossover thing is interesting, becasue when I first started testing this shield a week ago, I used a straight cable to hook the card to my laptop and it didn't work (yep, I had manually assigned an ip). Soon as I stuck it onto the router, it worked.

That's what made me think "Oh crap, you forgot to use a crossover" ... it certainly didn't work without one, yet both posts above say it probably should have.

It's no real biggy... it's just I don't have a network cable to my "lab" (read as: bed) and so to test this properly I need to schlepp into the other room and rearrange some furniture to be near power and router. Just laziness, actually.