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Cables and Connectors
This appendix lists cables that have been tested and verified for use with the
HP10/100 12 and 24 hubs. It also includes minimum pin-out information so, if
you wish to use an unlisted cable, you can verify that the cables used in your
installation are correctly wired. Note that each pin-out does not necessarily
match the pin-out for the corresponding HP cable, but cables manufactured
to follow the minimum pin-out will function correctly.
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.
Twisted-Pair Cable/Connector Pin-Outs
The RJ-45 ports (10 Mbit/s and 100 Mbit/s, both fixed and transceiver) on the
HP 10/100 Hub 12 and Hub 24 are wired as MDI-X ports. The type of twisted-
pair cable you connect to these ports (either “straight through” or “crossover”)
depends on the type of device at the other end of the cable.
The basic rule is
, when connecting same-type ports together (for example
MDI-X-to-MDI-X), use crossover cable; when connecting opposite-type ports
together (for example MDI-X-to-MDI), use straight-through cable.
These additional rules apply:
■
All twisted-pair wires used must be twisted through the entire length of
the cable. The wiring sequence must conform to AT&T 258A (not USOC).
See “Twisted-Pair Cable Pin Assignments” later in this appendix for a
listing of the signals used on each pin.
■
For connections to the 10 Mbit/s ports, you can use Category 3, 4, or 5
unshielded twisted-pair cable, as supported by the IEEE 802.3 Type
10Base-T standard.
■
For connections to the 100 Mbit/s ports, use Category 5 only, as supported
by the IEEE 802.3u Type 100Base-TX standard.
Roadhw0.bk : ROADHWB.FM Page 1 Thursday, May 28, 1998 5:40 PM
