RTX real-time Windows

IntervalZero’s RTX64 and RTX turn Windows into an RTOS

IntervalZero (formerly Ardence and Venturcom) RTX is the only software solution architected as a high-performance real-time extension to control Microsoft Windows. RTX is proven in thousands of demanding applications providing enhanced performance, control, scalability combined with unmatched dependability for: industrial automation; military/aerospace; test and measurement equipment; robotics; and many other industries while reducing system costs and speeding time to market.

Deterministic, hard real-time performance – plus the Windows user experience

Microsoft Windows offers a world-class interface and excellent development tools for embedded systems. However, for mission-critical threads that require hard real-time, deterministic responses – e.g. robots, vision systems, simulators, test and measurement systems – the Windows scheduler cannot deliver the necessary prioritization and control.

Replace dedicated DSP and FPGA hardware with a Windows PC

The untapped power of the latest Intel multicore processors is a match for demanding signal processing tasks, currently performed by expensive dedicated DSP or FPGA hardware, running incompatible and difficult-to-maintain firmware. RTX SMP allows users to harness the available power of up to 32 PC processor cores to take on the most demanding DSP tasks, in professional audio, video, medical imaging and simulation applications.


With IntervalZero’s RTX and RTX64 software, developers can take advantage of both the Windows environment and form factor, and also solve all their scheduling, prioritization and control challenges. RTX is a self-contained real-time subsystem that bypasses the Windows’ scheduler to provide the desired determinism and hard real-time response.

RTX architecture is a true extension in that it does not encapsulate Windows and does not interfere with or modify the Windows infrastructure. By maintaining this separation, the RTX real-time subsystem (RTSS) ensures that RTX-based applications survive Windows crashes.

The RTX real-time subsystem is designed around a high-speed scheduler that utilizes both priority-driven and preemptive algorithms. RTX supports up to 997 independent processes, with each process supporting unlimited threads. Fine-grained control over applications is assured with 128 levels of assignable thread priority.

RTX64 is a native 64-bit implementation of RTX, which affords access to 128GB of non-paged memory and genuine 64-bit performance

RTX for RealTime Windows spans multiple markets

Industrial Automation

Some of the world’s most demanding high-speed control and automation applications are running on standard Windows PCs using IntervalZero’s Embedded software solutions.

Customers have eliminated their dedicated “real-time” PCs, DSPs and PLCs in favor of an RTX-enabled unified Windows-based control system.

Using RTX, companies such as Siemens, Honda, MDSI and Hurco are delivering high-performance control systems for Computerized Numerical Control, Motion-Control, Material Handling/Sortation and Discrete Control.

The benefits include:

  • Reduced material costs
  • Reduced development times
  • More flexible and customizable systems
  • Reduced field-support costs

RTX loads as a driver to Windows and takes over the Windows scheduler and interrupt service. RTX processes have 128 priority levels – all higher than Windows and microsecond response time.

RTX has real-time support for all of the popular communication protocols such as TCP/IP, Modbus TCP, ControlNet/DeviceNet, Profibus, ASI, Industrial Ethernet and others.

Digital Audio

By combining Microsoft Windows, x86 multicore and IntervalZero’s symmetric-multiprocessing-enabled RTX software, Digital Media Systems OEMs and system owners take full advantage of the breakthrough capabilities of Soft-Control Architectures. Doing so enables them to achieve significant cost, productivity and quality improvements by replacing expensive, proprietary DSP/PowerPC/FPGA hardware with software components.

Benefits of Soft-Control Architectures to Digital Media Equipment OEMs

  • Reduction of 25-50% in Product Costs on Compute Platform
  • Replacement of many DSPs and FPGAs can drive out significant cost

Significant Reduction in Operational Costs

  • Reduced inventory costs for boards, DSPs and FPGAs
  • Reduced maintenance costs – software easily downloaded

Shorter Time to Market

  • Delivery of customized solutions at commodity pricing

Potential Vehicle to Open New Markets

  • Software allows flexibility in range of functionality offered

Benefits Digital Media OEM Can Pass On to End Users

  • More Competitive Price; Better Profitability
  • Better Product Experience
  • Multi-touch wow experience with Windows 7

Extensible Model Supports Easy Upgrades or System Fixes Improved User Productivity.


IntervalZero’s Embedded software delivers precision, control, and security to medical systems and devices.

Our control and real-time technologies are helping leading medical device manufacturers get to market faster, increase market share, and reduce system development and management costs for products such as patient monitors, imaging machines, device monitors, test and measurement systems, and device analytics.

In the Medical industry IntervalZero Embedded software is used to:

  • Create and maintain HIPAA compliant systems and devices
  • Facilitate movement to standards-based hardware and software
  • Secure, control and optimize Windows devices
  • Integrate image protection and instant on/off capability into Windows systems and devices

Military Aerospace

Using IntervalZero’s Embedded software on COTS-based systems is helping companies such as Boeing, Lockheed Martin, Northrop Grumman and Raytheon meet the demands of the US Military, US Government agencies, NASA and major airlines.

Developers of Embedded systems for Military and Aerospace understand the importance of designing for optimum performance, high reliability and long-term supportability. The trend toward COTS hardware and software is enabling developers to take advantage of standards-based designs to achieve these goals while maintaining control of budgets and project deadlines.

Common requirements for developers of military and aerospace systems include:

  • Use of standards-based hardware and software: IntervalZero’s embedded software solutions are designed for the Microsoft Windows development tools, operating systems and x86 processors.
  • High performance and reliability: RTX is a deterministic control solution for Windows-based systems. It restricts latencies to the single-digit microsecond range for optimized performance and high reliability, including failover.
  • Comprehensive Driver Support: RTX improves development efficiency by providing over 100 of the most common drivers – for communications and board support.
  • Support of past, present and future architectures: With product support from DOSx through Windows Vista, IntervalZero, a Gold Level Windows Embedded partner, is committed to long-term support and integration.
  • Risk mitigation: IntervalZero’s long experience and expertise in Embedded system development, along with availability of training, support and design services, ensure that even the most complex projects are completed on time and on budget.

Test and Measurement

IntervalZero’s Embedded software helps the Test and Measurement industry meet the demand for greater functionality and flexibility from their T&M tools at a cost-effective price. IntervalZero’s real-time software delivers greater functionality and flexibility and increases the performance of test systems that are increasingly reliant on PCs.


RTX/RTX64 Videos:

New RTX64 Architectural OverviewHow RTX Transforms WindowsRTX64 SchedulerRTX64 Memory Architecture 2014RTX64 Samples Overview

Customer Success Stories:

Key Features:

  • Robust, High-performance Windows RTOS Extension in Ring 0: sustained interrupt rates of 30 KHz
  • Smallest operational footprint – 250KB
  • Support for all standard Microsoft HALs: including ACPI compliant PIC, uni-processor and multi-processor APIC
  • Comprehensive Microsoft Windows operating system support: Windows 7, Windows Embedded Standard 7 and 2009, Windows NT, Windows XP Pro, XP Embedded, 2000, Server 2000 and Server 2003
  • Win32 API compliant: no need to use code wrappers for API mapping
  • Complete x86 CPU support: including multi-processor and multi-core in either shared or dedicated mode
  • Microsoft’s Visual Studio.NET 2003, 2005, 2008 and 2010: develop, compile and debug in the standard Windows development environment
  • Priority Inversion Avoidance with Promotion: ensures that lower priority threads do not impact application
  • Priority-driven or preemptive scheduling: assignable on a per thread basis
  • WinSock compliant TCP/IP stack: independent of Windows
  • High-speed Inter-Process Communication (IPC) mechanism