In embedded systems, hardware and software are tightly coupled to perform a specific function for an electronically controlled device. Embedded system testing plays a crucial role in the product development lifecycle. The process of verifying and validating the functional behavior of the embedded hardware and software, embedded system testing is often thought of as a check-the-box activity that is not given the attention it warrants.
The truth is, embedded system testing should be an omnipresent part of the software development process. If you are not conducting embedded system testing throughout the entire lifecycle, you run the risk of costly delays and a bumpy road to product launch. While it may sound daunting on the surface, by following a series of proven embedded software testing best practices, you can ensure a smoother process for a faster time to market.
Embedded software testing best practices
The key to the successful development of your embedded systems is a well-planned testing process. Here are six embedded software testing best practices that will keep you on track.
- Test early and often. Embedded systems testing often occurs as an after-thought—a potentially costly mistake. By incorporating testing early in the embedded software development lifecycle, you can identify design flaws when they’re simpler and less expensive to correct.
- Start with a static analysis. Static analysis testing involves the use of tools called “Static Analyzers” that runs through code to ensure that the coding is done in compliance with the associated coding standard. For example, if the programming language is C, you would use a validated Static Analyzer that checks coding compliance per language C.
- Complete unit testing. A unit is the smallest testable part of an application that typically has one or a few inputs and a single output. Unit testing involves checking individual units or functions of the software for errors. Unit testing is intended to verify the correctness of the program unit as a standalone entity. Catching errors in this early stage offers the least involved path to correcting them.
- Perform Integration testing. After the unit testing is performed, move on to integration testing, which checks the integration of the program units and subsystems to ensure that no new side-effects are introduced as a result of integration. These tests are also intended to address interface data and protocols including loss of communication and corrupted data as well as correctness of data passed between program units or subsystems. Note, integration testing in embedded systems should build incrementally as each unit is developed.
- Do regular dry runs. As the units are being built, run the test protocol that are developed to verify your requirements to identify not only test protocol errors but also potential software bugs. Dry runs should be ongoing throughout the product development lifecycle. When you have a stable build in place, do one final dry run before moving on to formal testing.
- Formally test the final system. While dry runs are considered a good embedded software testing best practice, a final system test is absolutely essential. With a release candidate in place, perform final system testing on production equivalent units under defined operating conditions by formally executing the test protocol to demonstrate that all requirements in the software requirements specification have been properly implemented.
By following the above best practices for your embedded software testing process, you’ll reduce the risk to both the company and the final user, cut costs associated with making corrections, improve performance and speed time to market. If you put your embedded system testing off too late in the process, you may end up designing a product that doesn’t conform to requirements, resulting in a blown budget and time delays.
At Sterling, we offer embedded systems consulting services to help you automate, maintain, monitor and test all your requirements in one place so you can see how they connect, interact and cross-link to each other—so you can develop quality embedded software with the industry’s highest efficiency and ROI.
For more information about embedded software testing best practices or to learn about our embedded systems solutions, contact us here. In the meantime, read our article about how to overcome collaboration challenges for your next project.