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AR# 18027

6.1i iMPACT - Programming an XC2C64 device fails; iMPACT indicates that the device is in read-protect mode


Keyword: 6.1i, iMPACT, program, CoolRunner, cool runner, 2C64, fail, read, protect, es, engineer, sample

General Description:

When I program an XC2C64, programming fails, and iMPACT indicates that the device is in read-protect mode.


This problem has been fixed in the latest 6.1i Service Pack, available at:

The first service pack containing the fix is 6.1i Service Pack 1.

For the ES parts, please use 5.2i Service Pack3 to work around this issue. This can be downloaded from the WebPACK site at:


Once registered, click the "Earlier ISE WebPACK Releases" link on the right to download the 5.2i version.

AR# 18027
Date Created 09/03/2007
Last Updated 12/15/2012
Status Active
Type General Article