Answers Database
XPLA2: Grouping signals in a fast module.
Record #7655
Product Family: Hardware
Product Line: R3000
Product Part: R3320
Product Version: XPLA2
Problem Title:
XPLA2: Grouping signals in a fast module.
Problem Description:
Urgency: Hot
General Description: How do I group signals in an XPLA2 fast module?
Solution 1:
Since signals that traverse the global ZIA incur either a 2nS (XCR320)
or 4nS (XCR960) delay, it is sometimes necessary to group timing
critical signals within a fast module.
This is accomplished using the property, FM_GROUP.
This property can be specified in a ABEL source
file or in a control file. Example: (please note the spacing)
fm_group siga sigb sigc
This instructs the fitter to place the list of signals specified with this
property in the same fast module. Note that the use of this property alone
does not specify a particular fast module for the placement of the signals,
it only indicates that these signals should be grouped together. To specify
a particular fast module for the group of signals, simply assign one of the
signals in the group a node or pin number from that fast module.
End of Record #7655 - Last Modified: 10/08/99 13:16 |
