RTOS ensures safety in critical tool processing

DDC-I Inc., a software development firm that works closely with the military and aerospace markets, is penetrating the general-purpose real-time OS market with a couple of OS that address safety-critical applications.

The Deos RTOS was created for military and aerospace applications that need safe operation and/or DO-178B Level A certification.

DDC-I's second RTOS, the HeartOS microkernel, was designed for general embedded and low- to mid-range, safety-critical applications.

Bob Morris, president and CEO, DDC-I, said: "Deos and HeartOS are the first commercial RTOSes built from the ground up to address the performance, reliability, security and certification requirements of safety-critical applications."

"There are comparable offerings from Wind River and Green Hills that address security, but not safety," he added.

DDC-I presents Deos in a modular, executable binary format that streamlines the test and certification process. "Unlike competitive RTOSes, which are delivered as source code, Deos does not have to be recompiled, relinked and retested to certify the application," he noted.

"DDC-I has been providing software development tools, run-time platforms and services to the safety-critical industry for more than 20 years," said Morris. "Now we are leveraging that expertise to offer turnkey safety-critical software platforms with tightly integrated, full-featured commercial-off-the-shelf RTOSes, which are platforms that address all aspects of development, certification and deployment," he added.

Deos and HeartOS are based on technology developed at Honeywell. The company has expanded its engineering staff and added core Honeywell engineers from the original Deos RTOS design team. The technology represents hundreds of person-years of engineering and IP development at Honeywell.

The near-term road map includes enhanced tool support, new programming interfaces and increased target support. DDC-I will also provide earlier certified artifacts up to DO-178B Level A.

Deos has deterministic, real-time response, guaranteed resource availability and a patented "slack" scheduling mechanism that achieves 100 percent CPU utilization.

Slack scheduling technology allows designs to use otherwise unused computation time from a slack account. Two sources of slack time exist: budgeted CPU time that goes unused during a thread's execution and unallocated CPU time. As threads execute and complete early, with respect to their worst-case budget, they donate their remaining unused budgeted time to the slack account. Conversely, as threads execute and wish to use slack time, they make explicit withdrawals. The Deos scheduler manages the deposits and withdrawals to ensure time partitioning and system schedules.

The HeartOS, scheduled for release in Q1 09, is a portable OS interface (POSIX)-compliant, deterministic RTOS optimized for small- to medium-sized safety-critical applications with tight space and time constraints. Certifiable to DO-178B Level A, the HeartOS is highly configurable and scalable, has a compact, portable TCP/IP stack and is available with a small-footprint, POSIX-compliant journaling file system.

- Nicolas Mokhoff
EE Times