1. VXWORKS operating system overview
1.1.vxWorks Operating System Introduction
Real-time multi-task operating system is a computer system that can perform its functions within a determined time, and respond to external asynchronous events. Multitasking Environment Allows a real-time application as a series of independent tasks to run, each task has its own threads and system resources. The VxWorks system offers high-efficient signal lights, messages, pipelines, and network transparent sockets, multi-processors and tasks. Another key feature of real-time systems is hardware interrupt processing. In order to get the fastest and reliable interrupt response, the interrupt service program ISR of the VxWorks system has its own context.
The VxWorks real-time operating system consists of more than 400 relatively independent, short refined target modules, and users can choose the appropriate module as needed to cut and configure the system, which effectively guarantees the security and reliability of the system. The system's linker can automatically link some target modules as needed. In this way, a number of applications that meet the functional requirements can be obtained by the on-demand combination between the target modules.
The basic composition module of the VxWorks operating system includes the following sections:
Efficient real-time kernel Wind
VxWorks Real-Time Core (Wind) mainly includes priority-based task scheduling, task synchronization, interrupt processing, timer, and memory management.
Ÿ Compatible with real-time system standard POSIX
VxWorks provides interfaces to support real-time system standard P.1003.1B.
Ÿ I / O system
VxWorks offers a fast and flexible I / O system compatible with ANSI-C, including Unix buffer I / O and real-time system standard POSIX asynchronous I / O. VxWorks includes the following drivers:
Network --- Network Equipment (Ethernet, Shared Memory)
Pipeline --- Task Communication
RAM --- Resident Memory File
SCSI --- SCSI hard drive, disk, tape
Keyboard --- PC X86 keyboard (BSP only supports x86)
Display --- PC X86 Display (BSP only supports x86)
Disk --- IDE and floppy disk (BSP only supports x86)
Parallel-port --- PC format target hardware
Ÿ This machine file system
Ÿ I / O system
VxWorks' file system is compatible with MS-DOS, RT-11, RAM, SCSI.
Ÿ Network characteristics
VxWorks networks can communicate with many of the network running other protocols, such as TCP / IP, 4.3BSD, NFS, UDP, SNMP, FTP, etc. VxWorks can allow task access files to other systems over the network and remotely call the task.
Ÿ Virtual memory (optional unit vxvmi)
VXVMI is mainly used to protect the designated memory area, such as memory block read only, etc., strengthen the robustness of the system.
Ÿ Share memory (optional unit VXMP)
VXMP is mainly used for shared semaphore, message queues, and memory blocks between tasks running on multiprocessors.
Ÿ Resident Target Tool
In the Tornado integrated environment, development tools work on the host side. Resident target enclosure, module loading, and unloading, the symbol table can be configured.
Ÿ WIND base class
The VxWorks system provides support for C and constructs system base class functions.
Ÿ 工 Tool Library
The VxWorks system provides users with rich system calls, including interrupt processing, timer, message registration, memory allocation, string conversion, linear, and ring buffer management, and standard ANSI-C libraries.
Ÿ Performance optimization
The VxWorks system records the utilization of the task to the CPU by running the timer, thereby performing efficient adjustment, reasonably arrange the operation of the task, gives a suitable task properties.
Ÿ Target agent
The target agent allows the user to remotely debug the application.
Ÿ Board support package
The board-level support package provides hardware initialization, interrupt establishment, timer, memory image, etc.
Ÿ VxWorks Simulator (vxsim)
Optional product VxWorks emulator, can simulate the operation of the VxWorks target, used to analyze the application system.
