Xilinx Answer #524 : PPR 5.1: Use of 5.0 guide file with XBLOX counters causes ERROR 9081

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PPR 5.1: Use of 5.0 guide file with XBLOX counters causes ERROR 9081

Record #524
Problem Title:
PPR 5.1: Use of 5.0 guide file with XBLOX counters causes ERROR 9081

Problem Description:

Solution 1:

PROGRAM: PPR

VERSION: 5.1

PLATFORM(s): All

SHORT DESCRIPTION:

Guide files created with XACT 5.0 that contain XBLOX counters may not work in 5.1.

ERROR MESSAGE:

*** PPR: ERROR 9081:
The following RLOC set(s) could not be placed on the device.

LONG DESCRIPTION:

PROBLEM:

A design that used to work in XACT 5.0 is run through XACT 5.1, and error 9081 is produced from PPR. The design contains XBLOX counters.

CAUSE:

In XACT 5.0, XBLOX would create RLOC counters for widths of 13 bits or more. In XACT
5.1, XBLOX does this for counters 6 bits and wider. If your 5.0 guide file has XBLOX counters of 6 - 12 bits, XBLOX 5.1 will create RLOC counters and thus there will be a significant different between the guide information and the netlist received by PPR
from XBLOX. The guide file has ripple counters (no RLOC's) and the new <design>.xtf
has RLOC counters. PPR, unable to resolve the discrepancy, fails.

SOLUTION:

Set the attribute USE_RLOC=FALSE for each counter that is affected by this change (this will cause them to be implemented as they were in 5.0, as ripple counters), or
create a new guide file using the 5.1 tools.

End of Record #524 - Last Modified: 10/21/96 17:32

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