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AR# 16490

5.1iSP3 iMPACT - "ERROR:iMPACT:583 - '1': The idcode read does not match..." is reported when an encrypted bitstream (.nky) is used


When I attempt to assign the encryption key to an XC2V1000-FG456 in the 5.1i software with Service Pack 3, the device is changed to an XCV1000. When I attempt to run operations on it after assigning the key, the following errors are reported:

"ERROR: iMPACT:583 - '1': The idcode read from the device does not match the idcode in the BSDL file.

INFO: iMPACT:629 - '1': Device IDCODE: 00000000000000000000000000000001

INFO :iMPACT:630 - '1': Expected IDCODE: 00000000011001000000000010010011"


This problem is fixed in the latest 5.2i Service Pack, available at:

The first service pack containing the fix is 5.2i Service Pack 1.

Alternatively, you can work around this problem as follows:

1. Assign the ".bit" file in iMPACT, select "Program", and then point to the ".nky" file through the Programming Options dialog box.

2. Open the ".nky" file in a text editor and add the letters "xc" to the beginning of the part name. (For example, "2v1000fg456" is changed to "xc2v1000fg456".)

These errors are related to the errors discussed in (Xilinx Answer 15721).

AR# 16490
Date Created 09/03/2007
Last Updated 02/04/2010
Status Archive
Type General Article