Embedded Systems

What is a Soft-Core Processor?

A soft-core processor is a microprocessor core that can be implemented entirely using digital logic synthesis. It is typically created on a programmable hardware like a field programmable gate array (FPGA). The key feature of a FPGA is that it is reconfigurable with different digital designs allowing functionality to be changed unlimited number of times by downloading a new file without physically changing the chip.

Development Cycle of Digital Designs with FPGAs

First, a digital design is encoded via schematic capture or a hardware description language (HDL). Then, the design is synthesized and transformed into a form that can be used to configure the FPGA. This form is normally called the configuration file. The configuration file is then used to configure the FPGA, which transforms the FPGA into the required digital solution.

FPGA Design Flow
Figure 1.0 FPGA Design Flow

For example, if the required digital design for the first input file is that of a microprocessor, then the resulting transformation of the FPGA yields a microprocessor. This type of microprocessor is termed to as a soft-core processor.

Figure 1.1 Soft-core processor design flow for FPGA

Once the FPGA has been transformed into a microprocessor, its usage patterns mirror those of a conventional (discrete) microprocessor. The processor must still be programmed using traditional programming languages and methods.

Figure 1.2 Programming of soft-core processor

Several traditional devices that are interfaced to discrete microprocessors like memory, buttons, switches, LEDs, etc., can also be connected to soft-core processors. The interface logic that is typically produced in the form of discrete components can be realized as logic instantiated in the FPGA along with the soft-core processor. Interface logic may include: Universal Asynchronous Receiver/Transmitter (UART), Serial Peripheral Interface (SPI), Inter-Integrated Circuit (I2C), etc.

Figure 1.3 Device interfacing to soft-core processor

Examples of 32 bit soft-core processors include: Xilinx Microblaze, Altera Nios II, LatticeMico32, etc.

Also read: Microprocessor vs Microcontroller, What are the Differences?

John Mulindi

John Mulindi is an Industrial Instrumentation and Control Professional with a wide range of experience in electrical and electronics, process measurement, control systems and automation. In free time he spends time reading, taking adventure walks and watching football.

Recent Posts

How AI and Machine Learning are Enhancing Electrical Control Processes

Electrical control processes form the backbone of industries, enabling seamless operations across sectors like manufacturing,…

17 hours ago

Standard Process Signals for Industrial Instrumentation

Industrial measurement and control processes employ standard process signals that are used throughout all the…

2 weeks ago

Top 5 Benefits of Combining CCTV Cameras with Biometric Systems

The integration of advanced technologies in security systems has become imperative for ensuring safety and…

2 weeks ago

Sources of Power Quality Problems

Power quality may be affected by a number of issues. Our discussion in this article…

2 weeks ago

Common Terms Used When Describing Power Quality Problems

Power quality has become an important issue to electricity consumers at all levels of consumption.…

2 weeks ago

What to Expect from PCB Assembly Services in China

The importance of printed circuit board (PCB) technology has escalated throughout the years with the…

3 weeks ago