Embedded Software vs Embedded Firmware

When building embedded systems, both embedded software and firmware are used in combination to implement code that controls the machine or device and allows it to perform its unique function.

Embedded software and firmware are similar in many aspects, but are quite different in their purpose and role within each embedded system. In this blog, we will go over how these embedded components function, their differences, and why each are vital to the embedded system’s operation.

What is an Embedded System?

An embedded system is a self-contained computer system that includes a combination of a microprocessor, memory, and input/output peripheral devices, and has a dedicated function within a larger mechanical or electronic system. Embedded systems may function as standalone devices or as part of larger systems, which is where it gets the name "embedded".

Embedded System Components

The components within an embedded system can be broken down into hardware and software components. The hardware can include the microprocessor/microcontroller, memory, inputs/outputs, timers, power supply, and so on, but without the software/firmware, these components wouldn’t serve much of a purpose on their own. The software and firmware are vital to the operation of the embedded system as it provides the basis for how the system runs.

As mentioned, both software and firmware are used to control and operate the system, but they do so in different ways and for different purposes.

What is Embedded Firmware?

Embedded firmware is a specific type of computer software programmed on a hardware device that provides low-level control for a device’s specific hardware. Firmware is implemented in non-volatile memory such as read-only memory (ROM) or electrically erasable programmable read-only memory (EEPROM) that cannot be easily modified or erased – hence the name “firm” – and is generally not intended to change once shipped. However, in more recent times, firmware is now commonly stored in Flash memory devices which is much easier to erase and reprogram and has greater storage capacity than its ROM/EEPROM predecessors.

The primary responsibility of the firmware is to boot a device and to supply the instructions for the device to function and communicate with various hardware parts. Essentially, the firmware is the code that runs on a piece of hardware and controls a processor and peripherals embedded within a larger device.

What is Embedded Software?

Embedded software is code that is programmed into the device’s main memory that is used to control the behavior of the embedded system.

Embedded software code is written specifically for the particular hardware that it runs on, meaning that it is constrained by the hardware’s CPU and memory capabilities. Any new hardware changes will require changes the software code. Embedded software programming language can consist of C, C++, Python, Java, JavaScript, etc.

Laptop computer with software code Photo by Luis Gomes

Embedded software is used to control the overall operation of the device and allows it to perform its designed function time and time again. In contrast to embedded firmware, embedded software controls the higher-level functions of the device, such as data processing and interaction with other devices.

Embedded Software vs Application Software

When understanding embedded software, it sometimes is compared to other types of computer software that many of us are familiar with, one being computer or application software.

Like previously explained, embedded software is a particular type of software that is exclusively built for a specific device/system that is restricted to that device’s specifications and doesn’t require an OS (operating system) to function. Any updates or additions therefore are strictly controlled. Application software, on the other hand, can generally run on various computer systems on top of the operating system, which can include MacOS, Windows, Linux, therefore the software doesn’t require as many restrictions. Generally, these types of applications can be updated fairly easily.

Example of Embedded Software

One example of how embedded software operates is by how a thermostat operates. The job of a thermostat is to detect temperature changes and activate the heat or air conditioning system within a home/office/etc. based on the settings input from the user. No other software or application can be installed on the thermostat device to change its behavior. Because of this, the software that controls the device is considered to be embedded software as it is embedded within the device.

Tools for Debugging and Developing Embedded Systems

Total Phase provides embedded systems engineers with host adapters and protocol analyzers to help with debugging and development of I2C, SPI, CAN, USB, and eSPI embedded systems.

I2C/SPI Host Adapters

For I2C and SPI system development, Total Phase offers I2C/SPI host adapters to allow users to program memory devices, as well as emulate master and/or slave devices to validate responses and communication occurring on the bus.

The Aardvark I2C/SPI Host Adapter is well-suited for general-purpose testing and memory programming, the Cheetah SPI Host Adapter is specialized for high-speed memory programming, and the Promira Serial Platform is best for advanced speeds and applications.

I2C/SPI, USB, and eSPI Protocol Analyzers

For testing and debugging I2C, SPI, USB, and eSPI systems, Total Phase offers protocol analyzers that monitor bus traffic in real time. This allows engineers to verify communication between devices and ensure there are no protocol errors or bugs.

The Beagle I2C/SPI Protocol Analyzer can non-intrusively monitor I2C and SPI traffic, and our line of Beagle USB Protocol Analyzers can monitor a range of USB speeds, each with their own unique features and capabilities for debugging specific USB applications. Total Phase also offers an eSPI Analysis Application for the Promira Serial Platform to easily monitor eSPI traffic in real time.

CAN Interface

For CAN system development, Total Phase offers the Komodo CAN Duo Interface, which can act as both a non-intrusive bus monitor as well as an active CAN adapter simultaneously.

To learn more about how our tools can assist with testing and developing your own embedded system, please contact us at sales@totalphase.com.