FPGA vs Microprocessor
Field Programmable Gate Arrays or FPGAs were once simple blocks of gates that can be configured by the user to implement the logic that he or she wants. In comparison, a microprocessor is a simplified CPU or Central Processing Unit. It executes a program that contains a specific set of instructions. The main difference between FPGAs and microprocessors is the complexity. Although both vary in complexity depending on the scale, microprocessors tend to be more complex than FPGAs. This is because of the various processes already implemented in it.
Microprocessors already have a fixed set of instructions, which the programmers need to learn in order to create the appropriate working program. Each of these instructions has their own corresponding block that is already hardwired into the microprocessor. An FPGA doesn’t have any hardwired logic blocks because that would defeat the field programmable aspect of it. An FPGA is laid out like a net with each junction containing a switch that the user can make or break. This determines how the logic of each block is determined. Programming an FPGA involves learning HDL or the Hardware Description Language; a low level language that some people say to be as difficult as assembly language.
The development and drop in price of semiconductors and electronics in general has slowly blurred the lines between FPGAs and microprocessors by literally combining the two in a single package. This gives the combined package a lot more flexibility. The microprocessor does most of the actual processing but it passes off the more specific tasks to an FPGA block. This lets you obtain the best of both worlds. The microprocessor can handle the general tasks while custom FPGA blocks give you the ability to incorporate unique blocks.
The improvement in electronics has broadened the coverage of microprocessors and FPGAs. If you really want to, you can use a microprocessor and make it do the work of an FPGA. You can also take an FPGA and make it work as a single logic gate. So for most tasks where you are choosing between a microprocessor and FPGA, you can probably make do with either one.
Summary:
- Microprocessors are more complex than FPGAs
- Microprocessors have fixed instructions while FPGAs don’t
- FPGAs and microprocessors are often mixed into a single package