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AR# 16083

6.1i PACE - If VREF and VR special pins are prohibited at different times, the prohibit commands are not cumulative


Keywords: PACE, prohibit, VREF, VR, cumulative, 5.1i, 6.1i

Urgency: Standard

General Description:
If VREF and VR special pins are prohibited using the function "IOBs -> Prohibit Special Pins", these commands are not cumulative. For example, if "VREF prohibit" is specified and "VR prohibit" is specified at a later time, the previous prohibit constraints are removed.


To work around this issue, copy the UCF constraints to a text file (e.g., WordPad), then paste the constraints back into the UCF after the latest prohibit has been specified.

This issue should be fixed in the next major software release (after 6.1i).
AR# 16083
Date 03/27/2007
Status Archive
Type General Article