Embedded Firmware Design: Why It's the Real Brain Behind Your Device

Embedded Firmware Design: Why It's the Real Brain Behind Your Device

Behind every intelligent device that you use nowadays, be it your fitness band or an industrial sensor, there is one component that quietly makes everything work. It isn't the stylish exterior and cool display of the device. It is the firmware. 

It is the good embedded firmware design that determines if the device is intuitive or complicated and unreliable. However, very few people who do not work in engineering know about the existence of firmware.

Understanding what embedded firmware design means when you develop a hardware project might save you months of wasted time and effort. Here is everything you should know about it in simple terms.

The Concept of Embedded Firmware Design Explained

Firmware, in other words, can be viewed as an interpreter between hardware and the external world. It goes without saying that the microcontroller of your gadget does not "understand" anything on its own. The person who writes the instructions for its operation on how to read data from sensors, blink the LED, establish contact with the Wi-Fi network, or shut itself off safely when the battery runs out of power – writes the code, which is called firmware.

As opposed to any ordinary software, which is developed for use in laptops, where there is a large amount of memory and computational capacity, firmware is usually limited by the very tight boundaries such as low memory and low computational capacity. It is due to the reasons mentioned above that embedded firmware design is seen as a separate discipline.

In a company like, embedded firmware design can be considered as base software that works in real time with the help of hardware. As a result, the behavior of devices meets all expectations even under challenging conditions.

Why Firmware Design is Important Than You Think

Many hardware companies put most of their efforts into making the actual hardware and give little importance to the firmware part of the process. It usually turns out to be a very costly decision. Let me explain:

It impacts reliability

Badly designed firmware causes the devices to crash, reset themselves, or interpret data from the sensors incorrectly. In case of critical hardware like industrial controllers or even medical devices, such bugs can become lethal.

It impacts time to market

When the initial firmware is designed keeping a proper architecture in mind, it becomes very easy for you to tweak and update it as required. Badly done firmware requires costly re-designing.

It impacts power consumption and efficiency

The proper firmware design has a direct impact on battery life and responsiveness of the connected device.

It impacts security

The connected devices are always under threat from some sort of malicious attacks. The firmware should be designed keeping security measures in mind from the beginning.

What Goes Into Proper Embedded Firmware Design

Designing firmware isn't a single task. It's a layered one. And it utilizes multiple diverse expertise areas.

System Architecture

Engineers build plans to show how hardware, firmware, and software pieces will all work together to meet performance specifications even before any code has been written. 

Without this planning step, design building it similar to building without building a foundation.

Design & Development

Requirements come to life as code in this step, and the aim is to make sure it all works well and security remains high, and it operates exactly to its requirements

The requirements for each particular device may differ by quite an amount, so one solution doesn't fit all.

RTOS, OS & bare metal applications

Applications are firmware on each device and depending on what device the firmware is for this might operate on: 

An RTOS like Free RTOS, Zephyr, Thread X, RTEMS, Lite OS or Nutt X or on bare metal for best control of the chip-each gives varying degrees of speed and real-time control.

Porting & optimization

It may sometimes be beneficial to move a piece of software from one device to another and it's up to the engineer to work out how the software will operate and to tweak it to get the most out of a variety of different types of hardware configurations.

BSP & Device Drivers

The BSP creates a connection between software and hardware so that they can 'talk' to one another, these drivers are coded individually for each specific device/module.

System integration & Security

The whole device hardware & software must communicate perfectly so the device can perform exactly to design. It must also work well without the owner becoming in any doubt of the device security.

Ready to build firmware that actually works the way your product demands?

Company's Embedded Firmware Design Procedures and Flowchart

All company's embedded firmware design projects will go through this following four stages:

1. Defining the system specifications - hardware as well as software capabilities needed and performance level requirements in order to fulfill the capability to design a very efficient system.

2. Developing the hardware - choosing micro-controllers, memories and interface and the hardware architecture blueprints, PCB layouts, and bill of materials.

3. Developing the software - actual firmware and applications build by various OS, Middleware and so on.

4. Product Finalizing - establishing final product functional and technical specifications and documentation including FSD, CDD, ESD, BOM.

There would be minimal chance of surprise when this methodology is followed and a truly "Product Centric" firmware can be developed than the conventional firmware development that forced to the product.

Regarding languages, controllers and operating system. It will typically ranges from C, C++, Java and Python for language, embedded controllers such as from the manufacturer list below as far as vendors are concern (Atmel, NXP, ST, Micro-chip, TI, Broadcom, Freescale, Nordic Semiconductor, MediaTek etc.) and of course embedded operating systems such as Linux, Windows, Open Wrt, RTOS and ARM Mbed OS for operating system. 

Additionally, embedded firmware design process involve networking protocol such as MQTT, CoAP or serial protocol such as RS232, SPI, I2C, CAN.

Common Mistakes Companies Commit While Handling Firmware

Some of the common mistakes made even by the most seasoned development teams include:

-Designing the firmware as a secondary issue instead of designing it along with the hardware

-Failing to understand the amount of testing required for real-time systems

-Failing to take scalability into account while selecting an OS or an architecture

-Neglecting security until the product is already released

-Lack of documentation of the design process, making it difficult to update it in the future

Most of these mistakes can be avoided if you work with a team that sees firmware design as a separate and specialized process.

Summary

Embedded firmware design is the invisible element that determines whether your hardware product will work properly as intended in practice. Whether it is the architecture of the system or choice of the RTOS, drivers, porting or security issues – everything counts. Rushing through or outsourcing such a complex procedure to non-specialized developers is a recipe for failure that will cost you money and more effort later. 

The systematic approach to embedded firmware design ensures that your product has the right start and will continue working properly for years.

When designing your next product that needs to be connected, prototyped or used in industry, do not neglect embedded firmware design. 

Contact our company and let us design custom firmware for your project!

Also Read

•  Building Intelligent Devices with Advanced Firmware Development Services

•  Electronics Hardware Development: Building Reliable Products from Concept to Production