Hardware in the Loop Testing On Your Desk

There is a continuous and growing demand for embedded systems based upon 16- and 32-bit microcontrollers. Whether in medical devices for laser surgery or pumps and actuators in automotive and industrial plants, these powerful, tiny devices have become a mainstay of embedded systems. We trust them to not only execute an incredible number of tasks but also that they will do this reliably. Therefore, it is no surprise that much engineering effort is spent on developing reliable and safe software for the application in question. Of course, this all needs to be accompanied by a well thought-through testing program that starts early in the development process. Otherwise, there is a risk that errors remain undetected until it is too late.
 
Typically, traditional cabinet-sized hardware in the loop (HIL) testers are only used at the end of the development cycle, during system testing, once everything is assembled. They are also an elaborate and expensive resource with which system or acceptance tests take place in cycles lasting anywhere between two and 12 weeks.
 

miniHIL

However, there is an alternative. Using a small, low-cost HIL system, deployed to the work bench of every development engineer, bugs are detected quickly and much earlier in the development process. This approach contributes to significantly higher overall software quality, which is where the miniHIL system from Protos comes in.

The hardware part of the system is a board slightly larger than an A4 sheet of paper. The microcontroller selected for your application, usually attached to a vendor’s evaluation board, is fitted to one side of the miniHIL. The other side features a powerful microcontroller upon which the functionality of your application is simulated. In the center of the board is a patch panel. This allows the I/O environment and communication of the microcontroller (system under test) to be linked to the simulation (software model of the application).
 

Testing without risking damage

The beauty of this approach is that every developer can trial and test application code without risking damage to expensive power devices and motor inverters. Developers can even use miniHIL to test software for sensor and actuator hardware that doesn’t yet exist.
 
An extensive and proven software toolchain supports the entire development process. During the creation of simulations and the generation of test cases, developers are provided with both textual and graphical reporting. miniHIL is also ideal for use in test automation solutions, such as continuous integration.
 
Within the classical V-Model software development process, miniHIL focuses on integration testing, enabling complete test cycles every 5-60 minutes. Additionally, because team members can execute tests in parallel, overall testing is significantly accelerated.

miniHIL also provides valuable assistance for system and acceptance testing. This is especially appreciated in projects with functional safety requirements, where customers report significantly simplified testing.