Learn how to use BeRTOS in your own application
- Have a look at the Tutorial section in order to discover how to create your first application, learn to use the basic modules, and much more!
- Case Studies
- BeRTOS is used in many industrial and commercial applications. Look at real applications developed by companies and discover what they think about BeRTOS in the Case Studies section.
- Example Projects
- Following some examples, you can learn something new very quickly. As such, we have supplied a list of complete projects in order to show how to use the modules and drivers available in BeRTOS. You can find them in the Example projects section.
BeRTOS Features Index
BeRTOS was born as a extremely modular, highly optimized and fine-tuned operating system for embedded programming. As a result, each module has its own scope and can be used alone or in cooperation with other modules.
BeRTOS currently supports a number of CPU families:
|CPU Family||Porting Status|
|ARM7TDMI||Atmel AT91SAM7, NXP LPC2XXX|
|Cortex-M3||Luminary Stellaris LM3S, ST Microelectronics STM32, Atmel SAM3|
|Atmel AVR||Most cpu supported (including Arduino)|
Have a look at the tutorial section for real world examples for some widespread development boards.
BeRTOS features both a preemptive and a cooperative kernel with synchronization primitives.
Embedded systems are mostly I/O bound systems. In these systems the microprocessor/microcontroller spends the most part of its computing power doing... absolutely nothing!
Since the system simply waits for external events to happen we decided to implement a strong and robust kernel with very low memory footprint and high modularity. This allows the kernel to be used on a variety of different CPUs, even the smaller ones.
Currently the kernel code is very stable.
- Preemptive and cooperative round-robin scheduling.
- Heap, for dynamic allocation of processes' memory.
- Stack process monitor, useful to prevent stack overflows.
- Inter-process messaging system. (with very low overhead)
- Binary semaphores with priority inheritance algoritm.
The kernel has a port layer (a single assembly function) that needs to be reimplemented each time a new CPU is added.
BeRTOS is not only a kernel, it aims to supply full operating system services. To achieve this we need at least some core drivers for every CPU port.
These drivers are: system timer, debug system and serial comm driver.
Adding CPU support for an already present CPU family is quite simple since hardware manufacturers share peripherals design between the same CPU cores.
Core drivers are completely supported on all platforms.
MCU Internal Peripherals Drivers
Since BeRTOS aims to supply full operating system services, for every CPU port we try to implement as much drivers as possible. This section covers the current development status for MCU Internal peripheral drivers.
|Atmel AT91SAM7 ARM|
|Atmel SAM3N ARM|
|Atmel SAM3X ARM|
|STmicro STM32F103xx ARM|
|Philips LPC23XX ARM|
|Stellaris LM3S ARM|
Generic Indipendent Drivers
BeRTOS supplies a full set of CPU independent generic hardware drivers. To achieve this all drivers are structured to have a hardware abstraction layer (HAL) that isolates CPU specific code and makes porting to new CPU easy.
Current driver list:
|AT25Fxxx Atmel flash memories||beta|
|FT245RL USB to parallel converter||beta|
|I2C with bitbang support||stable|
|Displaytech 32122A Graphic LCD||stable|
|Himax HX8347 LCD controller||stable|
|DC Motor with PID||stable|
|MPC41 digital potentiometer||stable|
|LM75 temperature sensor||stable|
|MPxx6115A pressure sensor||stable|
|TRIAC phase partialization||stable|
|PCF85974 I2C port expander||beta|
|RIT P14201 oled display||stable|
|Secure Digital card API||stable|
|Seven segment LCD display driver||stable|
|Stepper motor with ramps||stable|
|TAS5706A digital audio DSP||stable|
|TI TMP123 temperature sensor||stable|
|System timer API||stable|
|USB device API||beta|
File system development takes place in the fs directory.
File System: FAT
The FAT file system is the de-facto standard for removable devices such as SD cards or Memory cards. BeRTOS supports read and write operations on all existing FAT file systems, ranging from FAT12 to FAT32, with support to long file names. This file system is light and fast and allows to easily exchange data through external memory devices.
FAT module is highly configurable, for example it can be compiled in read-only mode for some space saving.
File System: BattFS
BattFS (Batt File System), has been developed to solve problems specific to embedded systems; BattFS is a file system that can be used on any physical media and it's optimized to reduce RAM and ROM usage to meet the strict design guidelines we have used with all the others BeRTOS components.
The goal is to have a filesystem suitable for little flash and eeprom memories (like dataflash), reliable, robust and capable of wear-levelling the memory pages to increase its life.
The code is in beta stage. Currently you can create files, append data to them but file deletion is still not supported. Wear-levelling is achieved by rotating a page every time it is written. Plans are to add even transactions (a whole write can be performed atomically).
- Scalability. The definitive file system for your embedded projects. Size doesn't matter.
- Data integrity. All data are protected with checksums and consistency is maintained in every operation.
- Written in ANSI C... so it can be used on any CPU.
BeRTOS Graphics and display management is very advanced. The system includes a complete graphic subsystem that can manage displays with support for fonts, bitmaps, clipping, text formatting and interactive menus, suitable for generating compact yet powerful GUI.
This system is composed of several modules ranging from simple graphic primitives to complex menu management functions.
|Simple windowing system||stable|
|Proportional and fixed size fonts||stable|
It's also available a console with command parser and command line history support similar to readline.
In embedded programming sometimes you have to cope with protocols, security systems and things like that. BeRTOS comes in help with a set of optimized portable algorithms:
|Cryptographically secure Random Pool||beta|
|Rotating hash checksum||stable|
|TEA (Tiny Encryption Algorithm)||stable|
|Stepper motor ramp generator||stable|
|RLE (Run lenght en/decondig)||stable|
To get up to date informations look at the algorithms source code.
Since BeRTOS can also be used in very tiny systems, some simple communication protocols has been developed.
This is the current status:
|Keytag (for 125KHz transponders)||stable|
|NMEA GPS protocol parser||stable|
|AX25 data link layer protocol||beta|
|TCP/IP stack implementation (based on lwIP)||stable|
|TFTP server module||stable|
For more information take a look at network directory.
BeRTOS supplies common data structures, implemented and optimized for low memory footprint and speed.
|Embedded-optimized dynamic memory allocator||stable|
|Unlimited length bit arrays||beta|
This section covers all BeRTOS modules that provide general purpose utility functions:
|Integers to/from host byte-order conversion||stable|
|C++ like exception handling in C||stable|
|Command shell with history||stable|
|Ini file reader||stable|
As usual, check source code for detailed reference.