User`s guide

38 MPC8240 and MPC8260 Emulation
Chapter 2: Connecting the Emulation Probe to a LAN
To set the 10BASE-T configuration
switches
Set switches S7 and S8 to ON unless one of the following
conditions is true:
•
If the LAN cable exceeds the standard length, set switch
S7 to OFF.
The emulation probe has a switch-selectable, twisted-pair
receiver threshold. With switch S7 set to OFF, 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 ON, 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 emulation 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 ON), 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 emulation probe is used on a
non 10BASE-T network (such as StarLAN) set this switch to
LINK BEAT OFF (OFF).