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//  This directory contains files which are too small to be projects in themselves.

//

//  Examples of such files might be:

//    prototype copyright files

//    parameterizable cell libraries

//    files which implement some interesting low-level function

//    files which are used as components in several projects

//

//  Each file should be self-documenting so that a quick glance would serve

//    to explain what it is and why it is here.

//

//  As a courtesy, each file could also have a small entry here to make it

//    easy to browse the directory looking for interesting stuff.

//

//  "opencores_copyright.v" is an example of a copyright file one might

//    include to control the use and abuse of a file stored in this web site.

//

//  "synchronizer_flop.v" is a behaviorial description of a 1-bit flop.

//    It should be manually instantiated in EACH AND EVERY MODULE which

//      uses a flop to synchronize a signal from one clock domain to another.

//    In real use, the user of this file will generate a simulation module

//      which will behave like a normal flop when presented with 1, 0, X, or Z.

//    This special-purpose module will NOT have setup and hold tests.  It will

//      NOT convert a valid value into an X due to setup timing being violated.

//    This module makes it possible to simulate gate-level netlists with

//      multiple clock domains without fear of making inappropriate X's.

//

//  "grey_to_binary.v" is an example of code which takes a binary number

//      and converts it to grey code, and vice versa.

//    This module has a parameter which describes how wide the operands

//      are.

//    This module does not use for-loops to generate the functions.  Instead,

//      it manually does the translation for widths up to 16 bits.

//    If the user wants fewer bits, the synthesis tool removes the extra.

//

//  "plesiochronous_fifo.v" is an example of a FIFO which transfers packets

//      between two clock domains.

//    The clocks are REQUIRED to be close to one-another in frequency.

//    The Writer is REQUIRED to skip writes every so often, to make sure that

//      the FIFO doesn't overflow.

//    This file instantiates the synchronizer_flop mentioned above.

//

//  "hamming_ecc_64.v" is an example of how to use 8 bits of redundant data to

//      correct single-bit errors and detect double-bit errors in 64 bits of data.

//    There are probably better ways to reorder the terms to reduce loads, and

//      to change the formulas to detect a larger percentage of likely errors.

//