nRF51 SDK v10.0.0
RTX support
This information applies to the following SoftDevices: S110, S120, S130

The SDK provides an implementation of an extension to ARM Keil RTX that is referred to as tickless mode. It allows waking up the MCU only when it is needed.


You should be aware of the following limitations when using RTX:

Cooperation with the SoftDevice

RTX shares the SVC interrupt with the SoftDevice. Therefore, it works on the same interrupt priority (UpperStack) as the SoftDevice API functions.


This example shows how to use the system function in interrupt handlers.

You must always clear the rtos_suspend variable in interrupt handlers that use RTX functions. Not clearing it might cause undefined behaviour.
void ***_IRQHandler(void);
*implementation of handler
rtos_suspend = 0;
osSignalSet (thread_id, SIGNAL); //example of system function

The following example applications demonstrate the use of RTX:

This document was last updated on Mon Nov 9 2015.
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