In the Standard FIFO post I talked about how a traditional FIFO works and supplied code for one. In this post I will be describing a First Word Fall Through (FWFT) FIFO. The main difference between standard FIFOs and FWFT FIFOs are that, as the name describes, the first byte written into the FIFO immediately appears on the output (See image below). This allows the first byte to be read on the next clock cycle without having to strobe the read enable. Additionally you can read the byte and strobe the write enable high at the same time so the next byte will be available to read on the next clock cycle.
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VHDL: First Word Fall Through FIFO
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