Scheduling

S140 SoftDevice Specification

The SoftDevice includes a scheduler which manages radio timeslots and priorities and sets up timers to grant timeslots.

Whether a Timeslot request is granted and access to the peripherals is given is determined by the following factors:
  • The time the request is made
  • The exact time in the future the timeslot is requested for
  • The desired priority level of the request
  • The length of the requested timeslot

Timeslot API timing explains how timeslots are scheduled. Timeslots requested at high priority will cancel other activities scheduled at lower priorities in case of a collision. Requests for short timeslots have a higher probability of succeeding than requests for longer timeslots because shorter timeslots are easier to fit into the schedule.

Note: Radio Notification signals behave the same way for timeslots requested through the Radio Timeslot interface as for SoftDevice internal activities. See section Radio Notification signals for more information. If Radio Notifications are enabled, Radio Timeslots will be notified.