FPGA and CPU are two different processors, each with unique characteristics and advantages. Here is an introduction and comparison of the two processors:
FPGA
Definition
FPGA, which stands for Field-Programmable Gate Array, is a type of integrated circuit that can be programmed or reprogrammed to the desired requirement after manufacturing. This means that it can be customized to perform specific tasks according to user specifications, hence the term "field-programmable".
An FPGA consists of an array of programmable logic blocks and programmable interconnects. The logic blocks can be programmed to perform complex combinational functions, or merely simple logic gates like AND, OR, XOR. The programmable interconnects allow these blocks to be wired together, like one would do on a breadboard, making FPGAs incredibly flexible and adaptable.
FPGAs are widely used in various applications such as digital signal processing, software-defined radio, aerospace & defense systems, medical imaging, computer vision, speech recognition, cryptography, and more. They are particularly useful in prototyping and validating new chip designs before they are manufactured on a large scale.
How does FPGA work
FPGA includes CLB(configurable logic module), IOB(input and output module), internal connection three parts, and has a different structure from traditional programmable devices. The FPGA implements the logic function by loading programming data to the internal static storage unit. The value stored in the storage unit determines the logic function of the logic unit and the connection between the modules of the logic unit or between the modules and the I/O, and ultimately determines the function achieved by the FPGA. Each lookup table is connected to the input end of a D flip-flop, which is used to drive other logic circuits or I/O, thus forming a basic logic unit module that can realize both the combined logic function and the sequential logic function. These modules are connected to each other or to the I/O module using metal wires.
FPGA Advantages
1, many customized chips using FPGA design, users do not need to project production can get suitable chips;
2, Using FPGA design ASIC circuit, short cycle, low cost, low risk, stable quality;
3, FPGA adopts high-speed CHMOS process, low power consumption;
4, FPGA architecture, flexible logic unit, high integration, wide range of application;
5, FPGA is compatible with the advantages of PLD and general gate array, and can realize large-scale circuits;
6, can be repeated on-site programming, low maintenance cost;
7, FPGA is parallel computing, can meet the multi-functional needs at the same time.
What is an FPGA used for
FPGA is suitable for large-scale parallel computing and hardware acceleration, and has the advantages of high speed, flexibility and configuration, and is widely used in communication, image processing, artificial intelligence, aerospace and other fields, such as 5G base station signal processing, image recognition and other scenarios.
CPU
Definition
CPU is the core component of computer system and one of the most important components of computer. CPU is short for "central processing Unit" and its role is to process and control all operations and functions in a computer system. The CPU is responsible for executing the instructions of the computer program and controlling the operation of the entire computer system. Most CPUs are microprocessors, meaning they are contained on a single integrated circuit (IC) chip. They can be found in various devices ranging from computers and smartphones to advanced scientific equipment.
The CPU is comprised of three main parts:
- The Arithmetic Logic Unit (ALU), which carries out arithmetic and logical operations.
- The Control Unit (CU), which manages the various components of the computer by interpreting the instructions from the memory and executing them.
- The Cache, a small amount of high-speed memory available to the CPU for storing information that's frequently used or might be used next.
How does CPU work
The working principle of the CPU is based on the process of obtaining, decoding, and executing instructions. When a computer program is running, the CPU reads instructions from memory and decodes the actions in the instructions. The CPU then performs these actions and stores the results back into memory or registers. This process is repeated until the computer program is finished.
The workflow of the CPU can be summarized in the following steps:
- Fetch refers to: the CPU obtains instructions from the memory and stores them into the instruction register.
- Decoding: The control unit decodes the instructions in the instruction register to generate the corresponding operation code.
- Execute: According to the requirements of the operation code, the operation unit performs the corresponding operation.
- Memory access: The operation result needs to be stored in memory, or the data can be read from memory for the next operation.
- Output: Output the processing result to the output device, such as the monitor or printer.
Cpu use cases
On the server side, the CPU is used to handle a large number of network requests, database operations and other tasks, providing powerful computing and data processing capabilities for the entire network. On the personal computer side, the CPU is a key component for running various software and games, providing high-speed computing and data processing power, so that the computer can meet the various needs of users. In terms of mobile devices, CPU is used to process a large number of user operations, sensor data, etc., providing strong support for various functions of smart phones.
Detailed comparison between FPGA and CPU
- Comparison of Functioning:
- CPU: CPUs operate in a sequential manner. They execute instructions one by one, in the order they are received. This is due to their fundamental architecture which is based on the Von Neumann or Harvard models.
- FPGA: FPGAs, on the other hand, have a parallel architecture. This means they can handle multiple instructions simultaneously, making them highly efficient for tasks that can be broken down into parallel tasks.
- Comparison of Flexibility:
- CPU: CPUs are general-purpose processors. They are designed to handle a wide variety of tasks efficiently. The flexibility of a CPU allows it to run different programs and execute numerous tasks, which makes it suitable for most computing applications.
- FPGA: FPGAs are specialized processors. They can be programmed to perform specific tasks, which makes them more efficient for those tasks than a CPU. However, once an FPGA is programmed, its functionality is set, which limits its flexibility compared to a CPU.
- Comparison of Speed:
- CPU: CPUs generally have high clock speeds (measured in GHz), which allows them to execute instructions very quickly. However, since CPUs operate sequentially, they may not be as fast as FPGAs for tasks that can be parallelized.
- FPGA: FPGAs have lower clock speeds (usually in the MHz range). However, because they operate in parallel, they can execute multiple tasks simultaneously, which can make them faster than CPUs for certain applications.
- Comparison of Power Consumption:
- CPU: CPUs are known for their high power consumption due to their high clock speeds and complex architecture.
- FPGA: In contrast, FPGAs are known for their low power consumption, especially when performing tasks they are specifically programmed for. This can make FPGAs a more energy-efficient choice for certain applications.
In conclusion, the choice between a CPU and an FPGA depends on the specific requirements of the task at hand. CPUs are better for general-purpose computing, while FPGAs excel at specific, parallelizable tasks.