PSOS
Encyclopedia
pSOS is a real time operating system (RTOS), created in about 1982 by Alfred Chao, and developed/marketed for the first part of its life by his company Software Components Group (SCG). In the 1980s pSOS rapidly became the RTOS of choice for all embedded systems based on the Motorola 68000
family architecture, because it was written in 68000 assembler and was highly optimised from the start. It was also modularised, with early support for OS-aware debugging, plug-in device drivers, TCP/IP stacks, language libraries and disk subsystems. Later came source-level debugging, multi-processor support and further networking extensions.
In about 1991, Software Components Group was acquired by Integrated Systems Inc. (ISI) who further developed pSOS - now restyled pSOS+ - for other microprocessor families, by rewriting the greater part of it in C. Attention was also paid to supporting successively more integrated development environment
s, culminating in pRISM+.
In July 1994, Integrated Systems acquired Digital Research
's modular real-time multi-tasking operating system FlexOS
from Novell
.
In 1999 Integrated Systems Inc. was acquired by Wind River Systems
, the originators of rival RTOS VxWorks
. Despite initial reports that pSOS support would continue, development was halted. Wind River announced plans for a 'convergence' version of VxWorks which will support pSOS system calls, and that no further releases of pSOS itself will be made.
NXP Semiconductors acquired pSOS for TriMedia
from Wind River and continued to support this OS for the TriMedia VLIW core.
RTOS.
In August 2007, RoweBots, a former partner of SCG and ISI, open sourced their pSOS+ compatible version called Reliant. It is available to all that wish to upgrade without applications changes.
The Xenomai project
supports pSOS+ APIs (and others traditional RTOS APIs) over a Linux-based real-time framework to allow existing industrial applications to migrate easily to a GNU/Linux-based environment while keeping stringent real-time guarantees.
Motorola 68000
The Motorola 68000 is a 16/32-bit CISC microprocessor core designed and marketed by Freescale Semiconductor...
family architecture, because it was written in 68000 assembler and was highly optimised from the start. It was also modularised, with early support for OS-aware debugging, plug-in device drivers, TCP/IP stacks, language libraries and disk subsystems. Later came source-level debugging, multi-processor support and further networking extensions.
In about 1991, Software Components Group was acquired by Integrated Systems Inc. (ISI) who further developed pSOS - now restyled pSOS+ - for other microprocessor families, by rewriting the greater part of it in C. Attention was also paid to supporting successively more integrated development environment
Integrated development environment
An integrated development environment is a software application that provides comprehensive facilities to computer programmers for software development...
s, culminating in pRISM+.
In July 1994, Integrated Systems acquired Digital Research
Digital Research
Digital Research, Inc. was the company created by Dr. Gary Kildall to market and develop his CP/M operating system and related products. It was the first large software company in the microcomputer world...
's modular real-time multi-tasking operating system FlexOS
FlexOS
FlexOS was a modular real-time multi-user multi-tasking operating system designed for computer-integrated manufacturing, laboratory, retail and financial markets...
from Novell
Novell
Novell, Inc. is a multinational software and services company. It is a wholly owned subsidiary of The Attachmate Group. It specializes in network operating systems, such as Novell NetWare; systems management solutions, such as Novell ZENworks; and collaboration solutions, such as Novell Groupwise...
.
In 1999 Integrated Systems Inc. was acquired by Wind River Systems
Wind River Systems
Wind River Systems, Inc. is a company providing embedded systems, development tools for embedded systems, middleware, and other types of software. The company was founded in Berkeley, California in 1981 by Jerry Fiddler and David Wilner. On June 4, 2009, Wind River announced that Intel had bought...
, the originators of rival RTOS VxWorks
VxWorks
VxWorks is a real-time operating system developed as proprietary software by Wind River Systems of Alameda, California, USA. First released in 1987, VxWorks is designed for use in embedded systems.- History :...
. Despite initial reports that pSOS support would continue, development was halted. Wind River announced plans for a 'convergence' version of VxWorks which will support pSOS system calls, and that no further releases of pSOS itself will be made.
NXP Semiconductors acquired pSOS for TriMedia
TriMedia (Mediaprocessor)
TriMedia is a family of very long instruction word media processors from NXP Semiconductors . TriMedia is a Harvard architecture CPU that features many DSP and SIMD operations to efficiently process audio and video data streams...
from Wind River and continued to support this OS for the TriMedia VLIW core.
Migration away from pSOS
In March 2000, rival company Express Logic released their Evacuation Kit for pSOS+ users, designed to provide a migration path to its ThreadXThreadX
ThreadX, developed and marketed by Express Logic, Inc. of San Diego, California, USA, is a real-time operating system . Similar RTOSes are available from other vendors such as VxWorks, Nucleus RTOS, OSE, QNX, LynxOS, etc...
RTOS.
In August 2007, RoweBots, a former partner of SCG and ISI, open sourced their pSOS+ compatible version called Reliant. It is available to all that wish to upgrade without applications changes.
The Xenomai project
Xenomai
Xenomai is a real-time development framework cooperating with the Linux kernel, to provide a pervasive, interface-agnostic, hard real-time support to user space applications, seamlessly integrated into the Linux environment....
supports pSOS+ APIs (and others traditional RTOS APIs) over a Linux-based real-time framework to allow existing industrial applications to migrate easily to a GNU/Linux-based environment while keeping stringent real-time guarantees.
External links
- Express Logic announcement of their Evacuation Kit, retrieved 2007-06-13