Sequencer Software Pack

Overview

The Sequencer is a utility that helps schedule tasks in systems without an OS.

Description and Usage

Description:

The Sequencer utility has been designed as a simple alternative to using a real-time operating system for less complex application cases. However, it does not cover all the services provided by an operating system.

The main features of Sequencer are:

• Task creation: Register a task so the Sequencer can call it.
• Task enable: Mark a task runnable from another task or an interrupt.
• Task pause/resume: Temporarily stop or resume a task from the scheduler’s viewpoint.
• Idle task: Optional hook called when no task is runnable.

Usage:

The start-up sequence can be split into five steps:

Step 1: Sequencer initialization

Initialize the Sequencer once with SEQ_Init() after basic hardware setup and before scheduling any tasks

Step 2: Task Definitions

Define tasks as short non-preemptive functions that return quickly, using either single-action tasks (one-shot actions) or state-machine tasks (advance one step per call with internal state).

Step 3: Registering Tasks

Register each task with a task ID bit and its callback function using SEQ_RegTask().

Step 4: Enabling Task Execution

To schedule work, set the task bit with a priority index (0 = highest) using SEQ_SetTask().

Step 5: Launching the Sequencer

Call SEQ_Run() inside the infinite loop to let the Sequencer process all pending tasks.