Timestamp bitstreams with USR_ACCESS

Automatically inserting a timestamp into a bitstream is really easy with the USR_ACCESS primitive. All you need to do is include the following constraint in one of the XDC files that you are using:...
  • Oct 29, 2015
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Understanding the INIT attribute for LUTs

Every Look-Up Table (LUT) implements a Boolean logic equation which is defined by the INIT attribute attached to it. When we wish to implement LUTs directly rather than allowing the synthesis tool to infer them, we must have an understanding of how the INIT attribute and the implemented logic function are related...
  • Oct 11, 2015
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Efficient frequency division with SRLs

One of the most common functions that is implemented inside an FPGA is clock division. For example, faced with having to divide a clock by a factor of 27 the FPGA designer will either use an internal PLL or write a piece of code like this:...
  • Oct 10, 2015
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