HP E3494A, Installation And Service Manual

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performance, increased LAN traffic, and even failure to power up (if the
BOOTP server becomes inactive).
7
Verify your HP processor probe is now active and on the network.
See "To verify LAN communications" on page 20.
To set the 10BASE-T configuration switches
Set switches S7 and S8 to CLOSED unless one of the following conditions is
true:
•
If the LAN cable exceeds the standard length, set switch S7 to OPEN.
The HP processor probe has a switch-selectable, twisted-pair receiver
threshold. With switch S7 set to OPEN, the twisted-pair receiver threshold is
lowered by 4.5 dB. This should allow you to use cable lengths of up to about
200 meters. If you use a long cable, you should consult with your LAN
cabling installer to ensure that:
•
The device at the other end of the cable has long cable capability, and
•
The cable is high-grade, low-crosstalk cable with crosstalk attenuation
of greater than 27.5 dB.
When switch S7 is set to CLOSED, the LAN port operates at standard
10BASE-T levels. A maximum of 100 meters of UTP cable can be used.
•
If your network doesn’t support Link Beat integrity checking or if the
HP processor probe is connected to a non 10BASE-T network (such
as StarLAN) set this switch to LINK BEAT OFF (0 or OPEN).
In normal mode (switch S8 set to CLOSED), a link integrity pulse is
transmitted every 15 milliseconds in the absence of transmitted data. It
expects to receive a similar pulse from the remote MAU. This is the standard
link integrity test for 10BASE-T networks. If your network doesn’t support
the Link Beat integrity checking or if the processor probe is used on a non
10BASE-T network (such as StarLAN) set this switch to LINK BEAT OFF
(OPEN).
N o t e
Setting switch S8 to OPEN when Link Beat integrity checking is required by
your network will cause the remote MAU to disable communications.
Connecting to the Host Computer
To set the 10BASE-T configuration switches
19