HP ProCurve 10Base-T 12 Installation Manual page 36

N o t e
Pins 1 and 2 must be a twisted pair.
Pins 3 and 6 must be a twisted pair.
Pins 4, 5, 7, and 8 are not used in this application, although they may be wired
in the cable.
N o t e
Incorrectly wired cabling is the most common cause of problems for LAN
communications. HP recommends that you work with a qualified LAN cable
installer for assistance with your cabling requirements.
HP 10Base-T Hubs Installation Guide B-2