1Core AVR

Embedded core written in C for AVR devices based on layered architecture with full integration of FreeRTOS kernel.

Getting Started

These instructions will get you a copy of the project up and running on your local machine for development and testing purposes.

Prerequisites

You'll need one of the following tools installed on your machine:

• Atmel Studio 7 - https://www.microchip.com/mplab/avr-support/atmel-studio-7
• Eclipse Embedded CDT with AVR plugin - https://eclipse-embed-cdt.github.io | http://avr-eclipse.sourceforge.net/wiki/index.php/Plugin_Download

You'll also need git to be installed on your machine.

Installing

You'll need to do the following:

• clone the repo to your local machine using: git clone https://github.com/loay-ashraf/OCore-avr.git
• create new project in your IDE.
• add your project root directory to compiler include path (in project toolchain settings).
• add the three main folders from cloned repo folder to the project: app, hal, rtos.
• scale down the layers according to the size of your application by removing unwanted modules (if you are using RTOS, modify the following file: rtos_config.h) - see Project Contents.
• remove unwanted modules simply by removing their folders in the rtos, ecu and mcu layer - see Project Layout.
• after removing unwanted modules from the project, rebuild the project to check that no errors are thrown by the preprocessor or the linker.

Notice: if using Eclipse IDE, you must add the following line in linker's "other arguments" field: -Wl,--gc-sections

Project Contents

The project contains the following software layers:

• RTOS layer
• Service Layer
• Hardware Abstraction Layer (HAL) which is then divided into: mcu layer and ecu layer

The RTOS layer contains:

• FreeRTOS kernel V10.2.1
• complmentary APIs like tasks, coroutines, queue, etc.

The Service layer contains:

• common functions like map
• common header files like std_types.h

The ecu layer contains:

• Distance APIs/drivers - Ultrasonic HC-SR04
• Character LCD API/driver - HD44780 controller
• Graphical LCD API/driver - ST7920 controller
• Keypad matrix API/driver
• RTCC API/driver - DS1307/DS3231 controller
• Servo API/driver

The mcu layer contains:

• softreset API - software reset using watchdog timer
• pwmin API - frequency and pulse width measurment
• dac API - PWM output using timers' fast pwm mode
• ac driver - analog comparator
• adc driver - analog digital converter
• gpio driver - digital I/O with external interrupts
• spi driver - serial peripheral interface
• timer driver - 8-bit timers TIMER0 and TIMER2
• timer16 driver - 16-bit timers TIMER1
• twi driver - two wire interface (I2C bus)
• usart driver - serial interface (USB,RS232)
• wdt driver - watchdog timer

Project Layout

└───OCore-avr
    ├───app
    │   ├───config
    │   └───examples
    │       ├───include
    │       └───source
    ├───hal
    │   ├───ddp
    │   │   └───avr8
    │   │       └───mega
    │   │           └───m16
    │   │               ├───ac
    │   │               ├───adc
    │   │               ├───gpio
    │   │               ├───spi
    │   │               ├───timer
    │   │               ├───timer16
    │   │               ├───twi
    │   │               ├───usart
    │   │               └───wdt
    │   ├───ecu
    │   │   ├───display
    │   │   │   ├───glcd
    │   │   │   │   ├───api
    │   │   │   │   ├───common
    │   │   │   │   └───driver
    │   │   │   │       └───ST7920
    │   │   │   └───lcd
    │   │   │       ├───api
    │   │   │       ├───common
    │   │   │       └───driver
    │   │   │           └───HD44780
    │   │   ├───distance
    │   │   │   └───ultrasonic
    │   │   │       ├───api
    │   │   │       ├───common
    │   │   │       └───driver
    │   │   │           └───HC-SR04
    │   │   ├───keypad
    │   │   ├───rtcc
    │   │   │   ├───api
    │   │   │   ├───common
    │   │   │   └───driver
    │   │   │       └───DS3231
    │   │   └───servo
    │   └───mcu
    │       ├───api
    │       │   ├───dac
    │       │   ├───pwmin
    │       │   └───softreset
    │       ├───peripheral
    │       ├───startup
    │       └───sys
    ├───rtos
    │   ├───config
    │   ├───include
    │   └───source
    └───service
        ├───include
        └───source

Built With

• Atmel Studio 7 - The official AVR IDE (for the AVR parts of the code)
• Eclipse Embedded CDT - 2021 - 03
• avr-gcc V5.4 - GNU AVR C compiler
• Make - auto-generated makefile

Tested With

ATmega16 running at 16MHZ (external crystal oscillator)

Fuse configuration:

• Lfuse: 0xFF
• Hfuse: 0xC9
• Lockbits: 0x3F

Authors

Loay Ashraf - loay.ashraf.96@gmail.com

License

This project is licensed under the MIT License - see the LICENSE.md file for details

Acknowledgments

Credits goes to:

The FreeRTOS project - https://www.freertos.org/