Hardware Abstraction Layer (HAL)

Table of Contents

• Overview
• Folder Structure
• Software
  • Software Design
  • Line of Code (LOC)
• License

Hardware Abstraction Layer (HAL) provides a platform-agnostic interface, abstracting peripheral interactions from specific hardware implementations. This promotes code reusability, scalability, and maintainability in embedded software development.

Overview

Folder Structure

Each peripheral shall follow this example directory structure.

.
├── adc
│   ├── doc -------------------------------- Software design documentation
│   │   ├── hal-adc-class-diagram.puml
│   │   ├── hal-adc-sequence-diagram.puml
|   │   └── images ------------------------- Software design images
│   └── public_inc
│       └── hal_adc.h ---------------------- Public interface
├── can
├── dac
├── delay
├── doc
│   ├── doxygen
│   ├── images
│   └── README.md -------------------------- Internal documentation
├── gpio
├── i2c
├── modbus
├── nvm
├── pwm
├── qei
├── README.md ------------------------------ This file
├── rtc
├── spi
├── system
├── timer
├── uart
└── wdt

Software

Software Design

Software design document available in the doc/ folder of each peripheral device. Each peripheral should have at least one class diagram and one sequence diagram illustrating the inputs and outputs expected for normal operation when using the interface.

The following example shows the GPIO class and sequence diagram,

GPIO Class Diagram

GPIO Sequence Diagram

Line of Code (LOC)

The total number of lines of code (LOC) for the header files.

File	Blank	Comment	Code
hal_uart.h	29	178	120
hal_can.h	24	166	105
hal_modbus.h	25	183	88
hal_i2c.h	23	174	84
hal_qei.h	25	159	81
hal_spi.h	24	191	81
hal_adc.h	22	110	71
hal_rtc.h	23	152	71
hal_gpio.h	21	121	59
hal_nvm.h	20	152	54
hal_system.h	20	129	51
hal_dac.h	20	136	47
hal_timer.h	18	104	47
hal_pwm.h	21	136	46
hal_wdt.h	18	104	44
hal_delay.h	12	72	16
SUM	345	2267	1065

License

Copyright (c) 2024 by TH Muda Engineering. All rights reserved.