FPGA programming: FPGA vs. Software programming
Table of contents
- What is FPGA?
- What is FPGA programming?
- Languages used to program FPGAs
- How is FPGA programming carried out?
- What you need to know to start programming FPGAs
- FPGA vs. Software programming
What is FPGA?
Even after it has been manufactured, an FPGA belongs to Embedded IC that users can change to carry out particular computer tasks. An FPGA is a highly customizable circuit that customers can alter to match the needs of their particular projects thanks to the gate array, a silicon chip with transistors that has no preset function. Because users can alter the circuit’s functionalities whenever they want to, anywhere, to suit their unique design objectives, an FPGA is field-programmable.
Users can repurpose the numerous gates found in FPGAs to build unique digital circuits. Memory controllers and communication interfaces are a couple of the gates found in an FPGA that customers can link to build custom circuits to suit their individual technological requirements. One of the main objectives of hardware architecture is the act of developing and curating the circuit structures.
What is FPGA programming?
The process of developing computer solutions with an FPGA is called FPGA programming. In order to create a working circuit that satisfies the requirements of the designers, the development procedures entail planning, developing, and implementing the architecture of gates. The end result of programming an FPGA is to produce a hardware circuit design that, when powered, produces a certain output. HDLs, or hardware description languages, are almost universally used for programming FPGAs.
Devoting time to FPGA programming can be quite beneficial for figuring out the procedures, circuit structures, and any faults that might occur when running hardware. This is why it’s crucial to properly plan your circuit designs and minimize any potentially time-consuming tasks. If the initial strategy turns out to be unsuccessful, this may involve debugging and modifying your hardware design.
Languages used to program FPGAs
VHDL：
VHDL has better behavioral descriptive capabilities as compared to other hardware description languages. For the purpose of describing and developing complex electronic systems from logical behavior rather than precise device structures, a strong behavioral descriptive capability is a crucial assurance. To realize some large FPGA design projects, several persons or perhaps several development teams must work simultaneously. The program structure and behavioral descriptive capabilities of VHDL statements show that it can facilitate the deconstruction of large-scale designs and the reuse of existing designs. It is possible to assess the functional viability of the developed system in the early stages of creating any system and to test the design at any time thanks to the comprehensive simulation statements and library functions of VHDL. VHDL’s rich set of simulation statements and library functions make it possible to check the functional feasibility of any system early in its design and to simulate the design at any time.
Verilog：
A Verilog HDL model of a circuit is the same as a Verilog HDL design for that circuit.Verilog models can represent actual circuits at various levels of abstraction.The following five model types correlate to the five levels of abstraction:
Models at the system level that implement the design model’s external features in high-level linguistic constructs;
Algorithm level: models that apply design algorithms to sophisticated linguistic constructs;
Models at the RTL level that describe how data moves between registers and is processed;
a model that describes logic gates and their connections at the gate level;
Switch-level: a representation of a device’s transistors, storage nodes, and connections between them.
SystemVerilog：
As a Verilog extension, SystemVerilog is a language for both hardware description and hardware verification. It can be used, like other HDLs, to define hardware patterns that you can later translate into digital code and upload into an FPGA to carry out particular tasks.
Static data, which remains constant over the course of a program, and automatic data, which the system generates as a result of a program’s design and execution, are both created by SystemVerilog. The main distinction between SystemVerilog and Verilog is that the latter models, designs, and tests electrical systems, whilst the former only models them.
How is FPGA programming carried out?
In FPGA programming, HDLs are used to alter circuits in accordance with the capabilities of the target device. HDLs translate codes into their own language using words and symbols, which the development program can then convert to data and load onto the FPGA. This gives it the necessary ability to carry out the tasks the FPGA must perform.
Writing code that is translated into a binary file is a requirement for both software development and FPGA programming. But unlike FPGA programming, which physically modifies the hardware, software programming optimizes a device to run software. By mastering both programming languages, you can succeed in a demanding, professional career.
What you need to know to start programming FPGAs
Background in digital logic design：
Hardware development, including the creation of circuit boards and microchip processors, uses digital logic design. This hardware processes data from navigational systems, mobile phones, and other high-tech systems, as well as human input and system protocol. You could contribute to the creation of computers, smartphones, and other personal electronic gadgets as a digital design engineer. Learn more about how training can improve function algorithms and binary conversion abilities by reading on.
Verilog/ VHDL：
VHDL is more verbose, academic, and sophisticated. Though it requires more writing, the rigor increases the likelihood that it will succeed. Verilog makes it easy to generate challenging bugs but is more complicated for conventional digital design. VHDL is increasingly prevalent in academic settings. Large semiconductor businesses use Verilog more frequently. Typically, the tools you are utilizing determine which one you should use. Certain well-known FPGA tools perform better with VHDL. With Verilog, some well-known ASIC tools perform better. Which is therefore superior depends on what you intend to use it for.
Let’s say you want to create modest projects with the popular Altera FPGAs seen in EE classrooms. Each HDL is supported by the free tools. But you might find that VHDL is primarily used by the user community. If you choose that language, there will be additional example code, reusable modules, etc. On the other hand, Verilog is now nearly universally used by large companies that conduct major chip design work. The robust synthesis, simulation, and verification tools have been Verilog-optimized. A recent addition to Verilog is SystemVerilog, which supports high-level system design and verification.
Simulation：
This paper explains how to simulate designs that are aimed at Intel FPGA devices using the software Intel® Quartus® Prime. Before configuring the FPGA device with the confirmed design, simulation enables you to test the behavior of your design. Your simulator receives input vectors that you provide, and over the course of the time period you specify, the simulator calculates and reports the anticipated associated outputs.
You build the RTL or gate-level representation of your design and testbench before engaging in simulation. The models from the Intel FPGA simulation libraries, IP simulation models, and any additional model libraries needed for your design must all be compiled. The Intel FPGA simulation procedure entails configuring your supported simulator working environment, constructing simulation model libraries, creating simulation files, running your simulator, and analyzing the output.
Analysis and Application：
FPGAs have a plethora of uses. They are employed in a wide variety of industries today, including data centers, automotive, aerospace engineering, defense, industrial IoT (internet of things), artificial intelligence (AI), and wired and wireless networking. These devices are frequently found in settings where users require real-time information. For instance, a home security camera must instantly transmit high-resolution photos with little delay to the homeowner’s smart devices. As consumers become increasingly dependent on instant information at their fingertips, these expectations will only rise.
Additionally, FPGAs can speed up processes that would otherwise be carried out by software. The ability to offload performance-intensive activities, such deep neural network (DNN) inference for artificial intelligence, is made possible by this, making FPGAs a useful tool.
FPGA Development Boards：
Field-programmable gate arrays (FPGAs), a type of programmable logic technology, are a crucial part of any contemporary circuit designer’s toolbox. FPGA development boards are the perfect solution to many of the issues the quickly developing technology sector is facing because of their broad capabilities and unique suitability for a variety of applications. Massive flexibility, cost savings over custom silicon, and improved performance due to hardware parallelism are the main advantages of programmable logic technology.
Verilog vs. C/C++ Comparison of notion of time：
The programming languages for software, including C/C++, have no concept of time. Any hardware design/description language (HDL), including Verilog, will incorporate a concept of time. Any HDL used to describe a digital circuit that includes primary digital building blocks (such as flip-flops, shift registers, memory, multiplexers, digital adder/subtractor/multipliers, etc.) will have a concept of time. When I use the word “time,” I mean that it can simulate a system that uses a clock (synchronous systems). These languages can, of course, also describe asynchronous systems. A hardware device that executes an algorithm is described in much more depth by any HDL like Verilog. Both the control and the dataflow are visible.
Describe an algorithm or using digital blocks：
On the other hand, higher level languages like C/C++ are used in the software industry. Their main function is to describe an algorithm, not to carry it out using digital building blocks in hardware. Having stated that, allow me to also add that High Level Synthesis (HLS), a design technique that uses the description of an algorithm as input and attempts to produce a hardware design that would do the same task, uses C/C++ and other languages.
Verilog was first introduced in 1984 to model digital systems, while the C language was first introduced in 1978 by Brian Kernighan and Dennis Ritchie. Both languages have developed independently as a result of demands for ease in designing digital systems (from manual layout and schematic-based design onward) and programming microprocessors/microcontrollers (from assembly onward). The notion of creating hardware using C/C++ was originally conceived as “behavioral synthesis (same as HLS)” in the early 1990s (Synopsys released Behavioral Compiler in 1994), but it has only recently begun to acquire wider popularity. The complexity of developing digital hardware is rising, but designer productivity is not growing at the same rate. HLS is being pushed as a methodology that can help in quick realization of parts of a design.
FPGA vs. Software programming
The distinction between FPGA programming and software programming is made explicitly by the way in which its instructions are executed. Instructions in software programming (C, Ada, etc.) are normally executed sequentially, but Verilog/VHDL instructions in FPGA programming are typically done in parallel (apart from blocking assignments in Verilog and variable assignments inside a process in VHDL). More significantly, FPGA programming or FPGA design involves creating digital logic circuits to control the behavior of FPGAs as opposed to software programming, which refers to the execution of a series of sequential instructions to carry out a given behavior in software. When you start programming FPGAs, you should discard the coding conventions used in software programming. To design and build synthesizable digital circuits on FPGA, many students simply transfer their software programming techniques (such as For Loop, While Loop, etc.) directly from software programming to FPGA programming. That FPGA coding behavior is awful.
With synthesis tools, creating this kind of code can be challenging. To make matters worse, some synthesis software keeps synthesising until RAM runs out, forcing you to restart it. In order to achieve the functionality you need, keep in mind the logic circuits that will be employed when programming an FPGA. As a result, before starting to code in FPGA programming, users usually first develop basic structures or logic circuits in accordance with the project’s needs.
