I am looking to have my arduino & beagleboard-powered 'brain' break out all pins and ethernet/usb connectors through one port on the outside of my enclosure (something like a chinese knock off of a harting DD series connector).
Question is, are there any problems with connecting shielded USB and Ethernet data cables via terminals (e.g. if using a DB25 in place of RJ45s, or USB connectors)? If My cables are shielded and grounded, can I use any connector with sufficient pin gauge?
I know his should be answered on the interweb somewhere, but can't find it...
It depends on a lot of things. It is not ideal but you might get away with it. The main problem is the reflections you will get at the impedance miss match between your cable and socket, and then again the miss match between socket and what ever you send it on to.
It is down to pot luck whether the reflections are bad enough to stop it working, make it unreliable with lots of retries or just be fine.
Thanks guys - that all makes perfect sense. I am only doing 10Mbps ethernet (will push to 100 if stable), and will only use the 4 pins utilised for TX/RX.