According to the company, the headline feature in version 9 is the ability to create completely statically allocated applications; no dynamic memory allocation is required. Other changes to FreeRTOS include an update that allows the OS to run on 64bit architectures, plus an update to the ARM Cortex-M RTOS ports that use the memory protection unit.
The enhancements in FreeRTOS V9.0.0 have been driven by feature requests and conversations with users. Real Time Engineers says this approach means the upgrades add value and will ensure that FreeRTOS continues to be the first choice small footprint RTOS.
Amongst the new features in the operating system is xTaskAbortDelay. The company says that RTOS tasks enter the Blocked state to ensure they do not use any processing time while they are waiting for a time to pass, or an event to occur. However, the xTaskAbortDelay() RTOS API function is said to make it possible for one task to force another task out of the Blocked state immediately. It notes this is desirable when an event occurring elsewhere in the system means the task in the Blocked state should stop waiting for an event, or if the task in the Blocked state has something more urgent to do.
