Increasing efficiency and reducing power consumption is key for modern embedded systems. To support these demanding needs SEGGER added tickless low power support to its popular embOS real time operating system. The embOS tickless low power feature reduces the power consumption for e.g. battery powered devices. It stops the periodic system tick interrupt during idle periods. Instead of having a timer interrupt for each system tick the timer is reprogrammed to be able to spend as much time as possible in low power mode.
One of the most common ways to reduce power consumption is to keep the processor in sleep (idle) mode for as long as possible. Typically an RTOS will wake the processor on a regular system tick - even if there is nothing to do. The embOS tickless low power support reduces power consumption by creating a variable length system tick which allows the processor to continue sleeping when there are no application tasks to execute.
Stopping the tick interrupt allows the microcontroller to remain in a deep power saving state until either an interrupt occurs, or the RTOS kernel has to transit a task into the ready state. This can make a huge difference in battery life.
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