Interphase Tech ispan 5535 pri Manual Do Utilizador

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Chapter 2: Installing the Hardware
iSPAN PRI PCI ISDN Users Guide
15
Requirements for MVIP Bus Electrical 
Termination
For systems with five or fewer MVIP bus connections and less 
than 90 pF load on the clock lines, it is adequate to place the 
circuit board that is the master clock source at one end of the 
cable and electrically terminate the MVIP bus only on the 
circuit board located at the other end of the cable.
N
OTE
The 
iSPAN
-PRI adapter is generally the master clock 
source, because it is connected to the network. In this 
case, place the 
iSPAN
-PRI adapter at one end of the 
cable.
On systems with more than five MVIP bus connections or 
more than 90 pF of load on the clock lines, both ends of the 
cable must be electrically terminated. No other boards should 
be electrically terminated. 
If the iSPAN-PRI adapter is at one of the MVIP cable ends, 
you must set the dip switches to their ON position (down) to 
complete the required electrical termination. Consult the 
relevant manuals for other MVIP adapters to correctly 
configure their specific electrical termination.
If you do not connect the iSPAN-PRI to an MVIP bus, you can 
leave the dip-switches, located close to the 40-pin double-row 
right-angled header, on any position.