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AR# 29798

Spartan-3A Configuration - Post Configuration CRC may not work in 9.2.04 or earlier software versions


The Post Configuration CRC feature does not seem to be working, and INIT goes Low when the device is powered up.

Are there any software requirements to use the feature?


The post_config_crc feature will require the BitGen software to calculate a CRC value which will be checked against the software.

Depending on device utilization, the software calculated CRC value can differ from the hardware calculated CRC value if the 9.2.04 or earlier tools are used. Not all designs will fail in the 9.1 and 9.2 software tools, and the issue is dependent on device utilization.

This issue has been resolved in the 10.1 and subsequent releases of the software.

If the 9.2.04 tools are required please install the following patch:


If a software version earlier than 9.2.04 is required the .ncd file should be run thought the 9.2.04 software version with the patch installed or the 10.1.x tools.

AR# 29798
Date Created 11/15/2007
Last Updated 12/15/2012
Status Active
Type General Article