RMOS3 real-time operating system

More performance through symmetric multicore processing
More system availability by means of memory protection
More industrial compatibility
More user-friendliness and serviceability

The reliable multicore operating system for hard real-time and maximum performance

The latest version 3.50 of the RMOS3 real-time operating system comes with even more performance, system availability and industry compatibility, as well as user-friendly and service-friendly features.

Features of RMOS3 V3.50

Configurable nucleus, optimized for SIMATIC PC Symmetric Multicore Processing Memory protection for more security and stability of operating system and application Support of latest technologies (APIC, HPET, UDMA, PCI) Defined response times in the lower microsecond range (approx. 3 microseconds) Deterministic behavior Priority-controlled multitasking Dynamic administration of task priorities with preemptive scheduling and round-robin counter for timesharing Task communication by means of priority-controlled mailboxes and messages Task synchronization by means of binary semaphores and flags Symbolic resource administration C/C++ runtime library User interface similar to MS-DOS (CLI, Command Line Interpreter) High-Level Language Cross Debugger (Eclipse, component of RMOS3-GNU) Cross-software development supported by GNU tools File system with long filenames, similar to Microsoft Windows

More performance through symmetric multicore processing (SMP)

RMOS3 V3.50 now also supports Core2 Duo processors thanks to the new symmetric multicore processing (SMP) mode. This mode makes it possible to implement complex applications that are simultaneously processed on multiple processor cores.

RMOS3 V3.50 ensures that the cores are symmetrically utilized so that a performance increase of up to 100% can be achieved on the SIMATIC PC with Core2 Duo processors compared to the single-core processor. A second PC, e.g. for visualization using RMOS3-GRAPHX, can be omitted without loss of performance. Applications can, if required, also be purposely linked to one core, in order to avoid effects such as deadlocks or CPU-hopping – without modifying the existing application.

RMOS3 V3.50 offers better performance on SIMATIC PCs with Core™2 Duo processors thanks to the symmetric utilization of the cores, or specific core assignment.

More system availability by means of memory protection

The memory protection functionality for RMOS3 offers excellent reliability for the execution of the user applications created from RMOS3-GNU V2.1 using the development tools.

• The applications are started in a separate execution level by means of an access management ("privilege level" mechanisms) and their memory accesses are managed by the operating system. The operating system code, data and stack are therefore protected from unauthorized access by user programs. This ensures reliable execution of the operating system.
• "Paging" mechanisms also protect the code areas of internal and third-party applications. This ensures reliable execution of all parts of the application and, in the event of an error, rapid localization of the actual cause. Time-consuming troubleshooting can therefore be avoided.
• This applies in particular to the new stack monitoring mechanism. It detects unauthorized exiting of the valid stack area. Unwanted memory accesses are therefore prevented.
• Null-pointer detection prevents the use of uninitialized pointer variables. Every access to the lowest page of the memory is detected. A page fault exception supports rapid error localization.

TCP/IP is already integrated into the centrally executed remote maintenance via Telnet and FTP services. This allows debugging and software updates both during the development and productive phase, e.g. for controllers used in locations that are difficult to access or isolated.

More industrial compatibility

High Precision Event Timers (HPET) are now supported for long-term accurate time output and logging of time events with minimum deviations. You then profit from the following advantages:

• In continuous operation (24/7), the deviations of the system time per week are reduced to approx. 9 seconds, meaning a 90% reduction compared to the standard timer.
• Selected events can be measured in femto-second resolution in order to ascertain program runtimes.

The driver for hard disk operation in UDMA mode offers fast data access. This means that greater volumes of data can be saved in a shorter time. APIC mode (advanced programmable interrupt controller) is now also supported for minimum response times to interrupts triggered by PCI modules. The 24 high-performance interrupts that are now available support optimized utilization of the interrupt resources and reduced shared interrupts on the PCI bus for enhanced real-time properties of the overall system. For the implementation of high-precision, cyclic control algorithms RMOS3 V3.50 now offers the possibility of implementing cycle times in multiples of 10 microseconds on a task-specific basis by means of function calls.

Further advantages of RMOS3 V3.50

Stable, robust and compact operating system which requires no administration and no maintenance by an IT department. Robust against viruses, as it is a highly specialist operating system. Extreme compactness facilitates short ramp-up times (less than 10 seconds) for prompt availability and small memory requirements enabling the use of low-priced hardware (RAM and bulk storage, e.g. CompactFlash).

More user-friendliness and serviceability

For users and service personnel, the expanded, configurable RMOS3 nucleus offers great convenience and shorter start-up times. It is optimized for SIMATIC PC and automatically recognizes the device type with its specific features. Your benefit: The same image can be used on different platforms without requiring any adaptation.

Apart from the already familiar additional functions of the nucleus, such as easy configuration using the initialization file (RMOS.INI) or user-friendly adjusting of serial and LAN interfaces, it offers the following functions:

• Activation of both processor cores for symmetric multicore processing.
• Configurable HPET support for system time signals with long-term stability.
• Simple start of the web server via RMOS.INI.
• Scandisk: checks the integrity of the mass memory on booting up to protect against data loss.
• Configurable UDMA support for fast access to mass storage.

RMOS3 even allows applications that were created for RMOS3 V3.0 (1993) to run today under Version 3.50. The RMOS3 high-level language interface is binary-compatible with older RMOS3 versions. This means you do not have to follow every update and you can still use older applications (e.g. PLM programs) today without having to re-compile them. Another advantage: no additional costs arising from service calls. 64-bit data types with formatted input/output and a timestamp function with nanosecond precision offer programmers more convenience when creating their applications. The user benefits from improved tools, e.g. for the evaluation and control of the operating system resources (via integrated RMOS3 debugger and resource reporter), determination of memory assignment, recording of the system loading or rerouting of the system console.

Comprehensive diagnostics functions support the developer and service technician during commissioning and the whole product life cycle:

• Project-specific designation of the kernel for fast identification of the automation system.
• Startup messages and exception/general protection messages are recorded in a LOG file for fast subsequent analysis of the system in the event of a fault.
• System flags for fast and reliable diagnosis of system states.