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AR# 13709

4.1i PAR - "Error: Place: 1906- The differential signaling Pair of IOBs are locked in a set of non-paired sites C8 and D8..."


Keywords: place, 1906, differential, non-paired

Urgency: Standard

General Description:
The following error message is issued in the PAR report:

"ERROR:Place:1906 - The differential signaling Pair of IOBs lip0_txflcclk_p_ext and lip0_txflcclk_n_ext are locked in a set of non-paired sites C8 and D8. This makes this design unroutable and the differential signaling pins will not work correctly. Please correct the design before continuing."

The error message is confusing, as it seems to indicate that D8 and C8 are NOT differential pairs. In this case, the signals were locked to pins C8 and E9, which are incorrect for the device.


The sites listed are a valid site pair. The error does occur due to incorrect site pairing; however, the error message is incorrectly listing one of the sites specified by the designer along with an unspecified site that should have been used, rather than citing the conflicting specification.

Check the related site pairings in the design to locate the true conflict.

This issue is being considered for a future software fix. Meanwhile, be aware that the message reported is misleading.
AR# 13709
日期 10/20/2008
状态 Archive
Type 综合文章