Kernel description

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Kernel description

7.1

Overview

The role of the demonstration kernel is mainly to provide a generic platform that controls

and monitors all the application processes with minimum memory consumption. The kernel

provides a set of friendly services that simplifies module implementation by allowing access

to all the hardware and firmware resources through the following tasks and services:

•

Hardware and modules initialization:

–

BSP initialization (LEDs, joystick keys, LCD, audio, Quad-SPI and compass)

•

Main menu management.

•

Memory management

•

Storage management (Quad-SPI Flash memory)

•

System settings

7.2

Kernel initialization

The first task of the kernel is to initialize the hardware and firmware resources to make them

available to its internal processes and the modules around it. The kernel starts by initializing

the HAL, system clocks and then the hardware resources needed during the middleware

components:

•

LEDs and buttons

•

LCD

•

Backup area

•

External Quad-SPI Flash memory

•

Audio codecs

•

MEMS

Upon full initialization phase, the kernel adds and links the system and user modules to the

demonstration core waiting to execute a menu entry point.

7.3

Kernel processes and tasks

The kernel is composed of a main task managed by FreeRTOS through the CMSIS-OS

wrapping layer:

•

Start thread: this task initializes the OS resources required by the demonstration

framework and then starts the demonstration.