HeartOS from DDC-I is a POSIX-based hard real-time operating system that is fast, light and well featured for most for small to medium embedded applications, including safety-critical applications.
Features
Modular & Scalable
POSIX Profile 51 Conformant
Small Footprint
Certifiable to DO-178, Level A
Supports 32 / 16 / 8 bit processors and DSP's
Network Support
Robust, Journaling Flash File System
The POSIX API
• Provides the required POSIX Interfaces
• Implemented using the provided core services
• Initialization Interfaces
• Initializes pre-allocated kernel and internal data structures
• Allows configuration of many of the provided services, including number of threads, stack size, priorities, etc.
• Run-time interfaces
• Provides an interface for the MIO to notify the OS that a system time tick has occurred
• Provides hooks for the MIO to notify the OS of exceptions or interrupts which have occurred
The HeartOS Core
• Provides framework to host the POSIX API
• Includes thread and list services as well as the interrupt and exception interface and the signal frame
• Highly Configurable
• Conditional compilation used to completely remove modules which may not be required (e.g. signals)
• Reduces the footprint
• Deterministic response
• All services designed to have a deterministic response time
• Scalable
• Kernel services designed to be scalable from 8 to 32 bit
The Middleware and I/O (MIO)
• Provides platform specific initialization of the hardware platform, including: timers, interrupts, and exceptions
• Initializes the HeartOS
• Forwards OS time tick interrupts to the OS
• Forwards unhandled interrupts or exceptions to the OS as necessary
The Hardware Abstraction Layer
• Provides an abstract interface to the processing core
• Simplifies porting to new processors
• Processor specific thread creation and context switching
• Interrupt enable/disable services
• Considered part of Middleware & I/O
