An Overlooked Alternative

September 9th, 2013 by

By Brian Carter
VP, Strategic Communications

Catching up on some industry reading over the weekend while watching my Red Sox thrash the NY Yankees, I ran across an article with a title that caught my eye: RTOS for Medical Devices 101. It discussed the benefits and risks of using commercial and in-house real-time operating systems (RTOSs) in medical devices.

Choosing whether to go with an “open-source, commercial, or in-house RTOS can be tough,” the article told me.

(Hmm…aren’t their additional alternatives to providing real-time performance? Something seemed to be missing from this “101” primer.)

The article continued:

“What is an RTOS? Why is it needed?

“An RTOS is software that helps a real-time application do its job. It’s analogous to Windows on a PC, which enables applications like Word, Internet Explorer, and Outlook to do their jobs. So, an RTOS is like Windows for the computer that’s within a medical device.”

(Hmm…if it’s analogous to Windows, why not look for a way to turn Windows into an RTOS, extending Windows capabilities to perform the RTOS part as well as the general purpose computing, all within a single Windows development environment?)

The article continued:

“The computers inside a device—typically referred to as an embedded system, are very different from PCs, so an RTOS has a very different job to do compared with Windows. Most notably, embedded systems have to perform their functions in real time as opposed to PCs, which do not have to meet any particular real-time constraints. Also, embedded systems are not as general-purpose as PCs, nor as resource-rich in memory, processing power, and peripherals. As a result, the job of the RTOS is focused on providing the application the resources it needs to execute, just as Windows is focused on the needs of a PC.”

“An RTOS provides applications with real-time scheduling (enabling applications to react to real-time events in a deterministic manner), real-time communications (enabling applications to send messages among parts of the application and to react to those messages in real-time), memory allocation, timer management, interrupt processing, device access, and other functions that real-time systems might need.

Hmm…IntervalZero’s RTX combined with Windows does all of the above. It extends Windows by providing a separate real-time scheduler that guarantees determinism and hard real-time.

Perhaps the RTOS decision-making process is not all that hard after all. Whether for medical devices and other embedded systems.


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