FPGA Primer

What is an FPGA?

A Field-Programmable Gate Array (FPGA) is a type of digital hardware that can be reconfigured to perform different tasks after manufacturing. Unlike a standard microcontroller, which runs fixed hardware, an FPGA is made up of a grid of logic elements and programmable interconnects that can be wired together to implement custom digital circuits. This makes FPGAs highly flexible, allowing engineers to design and optimize hardware behavior for specific applications.

How FPGAs Differ from Processors

Traditional processors, such as those found in computers or embedded systems, execute instructions sequentially (disregarding multithreading), following a program stored in memory. In contrast, FPGAs often perform multiple instances of the same task in parallel, mainly because the hardware is tailored for a specific use case.

How FPGAs are Programmed

FPGAs are programmed using Hardware Description Languages (HDLs) like VHDL or Verilog, which describe the digital logic and how different components interact. Unlike traditional programming languages that describe instructions for a processor, HDLs define how data flows through hardware circuits. Once the design is written, a synthesis tool converts it into a configuration file that programs the FPGA, physically wiring its logic elements and interconnections according to the specified design. This configuration file is called a bitstream.