We have detected your current browser version is not the latest one. Xilinx.com uses the latest web technologies to bring you the best online experience possible. Please upgrade to a Xilinx.com supported browser:Chrome, Firefox, Internet Explorer 11, Safari. Thank you!

AR# 406

XNFPREP 5.0.0: Possible cause of error 3520, invalid primitive


PROBLEM: XNFPREP 5.0.0 does not recognize legal primitives such as IBUF
and OBUF. Issues an error similar to the following:

The following are invalid primitives in part `3042APC84-7'.

Symbol Type = OBUF ; Symbol Name = U1 ;
Output Signal = OUT

Symbol Type = IBUF ; Symbol Name = IO3 ;
Output Signal = I8MHZ

Symbol Type = AND ; Symbol Name = M1/U2 ;
Output Signal = M1/$U2_O

Symbol Type = OR ; Symbol Name = M1/U1 ;
Output Signal = OOUT

SOLUTION: XNFPREP uses the file xlxlgl##.xnf (where ## is 2k, 3k, or 4k)
to identify valid primitives. If this file is missing or corrupted,
xnfprep will flag error 3520 on valid symbols. XNFPREP looks for these
files in the local project directory and in XACT/DATA. Verify that there
is not an invalid file in the local directory and that a valid one is in

AR# 406
Date 03/31/1997
Status Archive
Type ??????