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AR# 33756

ISE software 11 - buffer_type in the UCF not supported for AUTOBUF starting in 11.4


Keywords: ngdbuild, constraints, file

Starting in 11.4 (planned to be released in early December), support for AUTOBUF will be decreased.


New behavior for 11.4 includes:

- Existing designs with the buffer will still work if the buffer_type was set in the RTL
- Designs that set the buffer_type via UCF will fail with an error message
- Documentation for AUTOBUF will be removed from the Libraries Guide
- XST will no longer infer the buffer-type
- The Language Templates in Project Navigator will no longer list the component

If you are planning a new design, please avoid using the AUTOBUF primitive and instead use the explicit buffers (BUFG, IBUF, BUFIO, etc.).
AR# 33756
Date 11/04/2009
Status Active
Type Known Issues
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