Description: Z-Wave Wireless IoT Expert
To use an RTOS for your embedded project, or Not! That is the question poor Yorick ! I digress from my usual focus on Z-Wave to discuss the general topic of using a Real-Time Operation System (RTOS) for simple embedded IoT devices. The question is moot for Z-Wave since the protocol has FreeRTOS built-in starting with the release of the 700 series. For the moment at least, the choice is To RTOS!
My focus in this post is on small IoT devices like sensors, dimmers, window shades, to more complex devices like thermostats and door locks. Using an RTOS for simple devices like these brings different requirements than say a full Operating System like Windows or Linux. The purpose of an Operating System (OS) is to provide common resources to an application – things like memory management and insulating the application from hardware . The term “Real-Time” comes from basic concept of dividing up the resource
In the beginning Z-Wave ran on an 8-bit MCU with limited FLASH and RAM which meant life without an RTOS due to CPU performance and memory limitations. The Z-Wave protocol was built on “ Bare Metal ” and thus interrupt driven with a tick-timer and drivers to provide basic services. The 700 series opened the world of a 32-bit RISC MCU and significantly more memory which enabled the use of an RTOS as the foundation of the Z-Wave protocol.