Software and hardware architecture is determined by „what-if“ analyses during system design. Comparing design alternatives in no time provides the ability to design a system architecture which still fulfills all of its real-time requirements. Beyond that, conclusions about execution times on tasks, function and code segment level can be drawn, which can be incorporated into a design specification for subsequent developments.

The INCHRON Tool-Suite supports you in analyzing the dynamic behavior and helps you to validate the design specifications of your software. Test methodology intended for release tests can be employed throughout the whole software development life cycle. This enables you to locate and eliminate dynamic flaws and performance bottlenecks at an early stage and thereby validate and optimize your software yet before building a prototype.

In many projects, the degree of freedom to design HW is limited and consequently the main emphasis is put on software design. Hence, engineers want to find the optimum software architecture (definition of tasks and interrupt service routines, scheduling, etc.) while being limited in adapting the HW architecture. Even though the focus is on the software architecture, changes in the HW architecture, like different size of memory and a different microprocessor within a given processor family, etc., require thorough investigation in order to find the most cost-effective solution.

System Engineers use INCHRON Tool-Suite for system design by performing what-if analyses combined with in-depth investigations to make design decisions on software architecture taking into account different underlying hardware architectures. Before the real code is written, engineers assign execution time budgets to tasks, functions and code segments of the intended software structure to simulate and analyze the dynamic behavior of different software architectures until engineers have designed the most suitable software architecture. Moreover, system engineers make well-founded decisions on execution time requirements of tasks, functions and code segments as design input data to avoid real-time problems.

During software coding, engineers replace more and more time budgets of the initial software architecture with coded software modules. INCHRON Tool-Suite executes these modules on a virtual prototype whereby chronEST automatically calculates the execution time of these software modules considering the hardware architecture. Thus, engineers are able to perform an in depth analysis of the dynamic behavior of embedded software, investigate and avoid potential runtime problems as well as optimize and verify the system before building a real prototype. Simulating the design under stress conditions quickly reveals bottlenecks and shows the amount of resources remaining for future software expansions. The performance can be analyzed early without having a real prototype.

Very often, engineers jump-start development projects by reusing software from previous projects. As a result, engineers want to quickly analyze the re-usability of legacy code and to assess the R&D efforts to adapt such legacy code to be used within new applications. INCHRON Tool-Suite in combination with chronEST perfectly addresses these issues. For new products, engineers design a new software architecture, which includes the legacy code. While simulating such “hybrid” software architectures, engineers can quickly assess the reusability of code. Further more, engineers get a deep insight into the dynamic behavior of legacy code.

In a fast changing environment, products need to be quickly modifiable to implement new higher valued features. As a result, engineers have to make fast feasibility studies in order to economically assess the R&D efforts for implementing a new feature. Using INCHRON Tool-Suite and chronEST, engineers can quickly integrate their estimated execution time of a new feature into the current software architecture of the embedded system. Thus it is possible to analyze the impact of a new feature in the dynamic behavior of the total embedded system, even before writing the appropriate software code. Such an analysis of utmost importance since a new feature may negatively impact the execution time of other features resulting in a non-real-time-compliance embedded system.

INCHRON Tool-Suite helps to reduce the number of redesign cycles by enabling system engineers to analyze, optimize and verify the design very early during development even before a real prototype is built. Less redesign cycles, directly reducing the time-to-market and simultaneously improving the chances of attaining the targeted market launch date.

By employing INCHRON Tool-Suite, engineers can analyze and optimize a design without being forced to build a prototype, thus reducing redesign cycles. Avoiding project delays and improving time-to-market have a direct impact on the R&D cost.

INCHRON Tool-Suite simulates embedded software on different hardware architectures, enabling engineers to select the most cost effective design.

INCHRON Tool-Suite increases the quality of embedded systems by avoiding real-time problems. Engineers can detect and eliminate real-time problems at the development stage and thereby dramatically reduce the risk of product recalls.

When confronted with new requirements, engineers have to make a fast estimation of the impact of new features. With INCHRON Tool-Suite, engineers can integrate the requirement of a new feature into the original system specification to analyze and predict the impact without building a prototype. INCHRON Tool-Suite provides a prompt answer to the question whether a new feature can be integrated into the existing design or whether a major redesign is necessary.

The behavior of the defined system can be examined with the optional module chronSIM in a simulation. The INCHRON Tool Suite represents the reaction of the embedded system to the given stimulation in detail. A special emphasis is the investigation of the task behavior and the tracking of data flows and event chains by the system.

The optional module chronVAL examines the embedded system analytically. The adherence to given real time requirements is calculated for the worst case. Innovative patent protected procedures are used to consider the run time behavior of the tasks, the dependence among themselves and the worst possible suggestion.

The optional module chronOPT facilitates automatic tuning of different kinds of system model parameters in order to adjust its real-time behavior regarding certain real -time requirements.

For the simplified modeling of complex systems and also for the acceleration of simulation a part of a large system can be replaced by the chronBUS in the INCHRON Tool Suite. To communication buses attached controllers are reduced thereby to their communication behavior.

With this option the INCHRON Tool-Suite supports the modeling of AFDX networked systems. Virtual links can be defined and AFDX Message can be modeled. The resulting system can be examined with chronSIM and chronVAL.

In chronSIM the execution times of code blocks have to be entered manually. chronEST allows the execution times to be determined automatically from your partial or complete source code, factoring both the architecture of the target processor (register set, pipeline architecture etc.) as well as optimizations done by compilers.

INCHRON Tool-Suite comes along with an extensive library of target platforms (microprocessors, real-time operating systems, etc.). This library is continuously maintained and extended by INCHRON. Please contact your INCHRON Tool-Suite partner if the integrated library does not support your intended platform.

The information, recommendations, descriptions, and safety notices in this technical manual are based on INCHRON experience and judgment with respect to operation and maintenance of the described product. This information should not be considered as all–inclusive or covering all contingencies. If further information is required, INCHRON GmbH, should be consulted.

No warranties, either expressed or implied, including warranties of fitness for a particular purpose or merchantability, or warranties arising from the course of dealing or usage of trade, are made regarding the information, recommendations, descriptions, warnings and cautions contained herein.

In no event will INCHRON be responsible to the user in contract, in tort (including negligence), strict liability or otherwise for any special, indirect, incidental, or consequential damage or loss whatsoever, including but not limited to: damage or loss of use of equipment, cost of capital, loss of profits or revenues, or claims against the user by its customers from the use of the information, recommendations, descriptions, and safety notices contained herein.

INCHRON Tool-Suite is designed to run on standard x86-based PC hardware. In order to run INCHRON Tool-Suite, your computer must meet the following minimum requirements:

INCHRON Tool-Suite requires Microsoft Windows XP in German or English language with Service Pack 2 installed or alternatively Microsoft Windows 7, 8 or 10.

For displaying control flow graphs the external software GraphViz is used. Absence of these 3rd party software packages does not impair proper operation of INCHRON Tool-Suite, but will only affect the displaying and printing of graphs. These 3rd party software packages can be installed directly from your INCHRON Tool-Suite CD-ROM.

The INCHRON Tool-Suite comprises different tool options namely chronSIM, chronVAL, chronEST, chronBUS, chronVIEW, chronOPT and chronView which may be used separately. The usage of any of these tool options requires a license option. The license may be available either as USB dongle or FLEXlm license. In both cases single-seat as well as network licenses are possible.

The configuration of a license server and the management of licensing options to be used is done with the Manage Licenses dialog from within the INCHRON Tool-Suite. Server license allocation may be limited by restricting any workstation to a single instance of the Tool-Suite application see Section 4.4.1, “General Settings”). Changing the current set of INCHRON Tool-Suite tool license options is done as follows:

Alternatively to using a USB dongle the Flexera FLEXlm® license mechanism may be used. A FLEXlm® license is bound to the host ID of your computer or the network server respectively. The FLEXlm licensing mechanism requires no additional Flexera software to be installed on your computer.

In large installations it is common that a company acquires a different number of licenses for e.g simulation (chronSIM), validation (chronVAL), and trace analysis only (chronVIEW). In such a case it is important that each installation of INCHRON Tool-Suite occupies only the required tool license options.

The selection of required license options can be changed as follows:

When started chronVIEW comes up with the Simulator Window. There you can import trace files immediately. This function is also contained in chronSIM. Thus for comparison of simulation results with measured traces once in a while you do not need to change the license options every time.

The installation verification is exemplified with an example project.

The connection to the DOORS database is based on Open Services for Lifecycle Collaboration (OSLC). It supports Requirements Management (RM), version 1.

IBM Rational DOORS offers this interface via the DOORS Web Access (DWA). The Tool-Suite requires at least DOORS 9.3.0.4 and DOORS Web Access 1.4.0.4. The following sections assume that these DOORS components have been installed. Additionally administrative permissions on the DOORS database are required for configuration.

The INCHRON Tool-Suite OSLC integration can be configured using a web browser. Select Settings → IBM Rational DOORS Settings... to start the configuration. On an unconfigured system the Initial Configuration Page will also be shown when selecting any other DOORS-related operation.

At the top and the bottom of the page a Save Configuration button is located. It stores the actual values to an XML encoded file.

The OSLC based connection to the DOORS database is a two-way communication. Therefore the Tool-Suite also opens a local TCP port and listens for connections. In the General section this port can be configured. The port is only reachable from localhost.

The Log Level can be configured. All messages are shown in the Log Messages Window of the Tool-Suite.

The connection to the DOORS database has to be configured in the DOORS Web Access section. The options are:

At the bottom of the configuration page the Save Configuration button is repeated. Hyperlinks provide access to the INCHRON Support and to the INCHRON web site.

The configuration of the connection to the DOORS database can be shared by multiple users by performing the following steps:

Now every user running this Tool-Suite installation will use the set configuration.

In project mode the INCHRON Tool-Suite window is presented as main window for user interaction. It presents different views for editing different aspects of a system model. A detailed description of features of the project mode is subject to Chapter 6, System Modeling.

The simulation mode requires the chronSIM license option and is entered by loading and compiling a simulation project from the project mode window. A detailed description of features of the simulation mode is subject to Chapter 7, Simulation. For a better understanding please open the example project from the INCHRON distribution:

Together with the Real-Time Simulator window the Simulation Control window appears.

The purpose of the Simulation Control window is to enable of disable specific breakpoints. It may be toggled with Windows → Show Simulation Control .

The chronSYNTH mode provides interactive modeling features for simulation diagrams. This facilitates model changes from within the simulatior window, which trigger a simulation and an immediate update of simulation diagrams for an immediate update on any effects of model changes. For that purpose, the context menus of simulation diagrams have a sub-menu offering several actions for model modifications. See Chapter 10, Interactive Design of Dynamic Architectures for details. Any changes can be applied by clicking the Run Simulation toolbutton in the Project Window which will restart of the simulation. Once finished the diagrams in the Simulator window will be updated accordingly.

The validation mode requires the chronVAL licensing option and is entered from the project mode window. A detailed description of features of the validation mode is subject to Chapter 8, Validation. For demonstration open the validation example project:

The chronVIEW license option is a restricted mode for using the functionality of INCHRON Tool-Suite simulation diagrams on simulation traces. This includes viewing saved chronSIM traces and the import of custom CSV traces.

In chronVIEW mode INCHRON Tool-Suite will start with a simulation viewer window. The configuration of a chronVIEW license option is described in Section 2.2.2, “License Management”.

The usage of the diagram functions is like described in Section 7.2, “Running a Simulation”.

Opening a simulation trace is done as described in Section 7.8.2, “Loading a Trace-File”.

The import of custom trace files includes the automatic creation of a basic system model which may be opened in the model editor via Edit Simulation Model (chronSIM license option assumed). Management of real-time requirements for imported traces is also available after opening the model editor.

You will find the example used in this chapter in the doc\examples\OIL subdirectory of your Tool-Suite installation.

The following example will create a project file in the same directory as the OIL file. If you prefer to leave your installation directories untouched, or if you don't have write permissions in this directory, copy the entire OIL subdirectory to a temporary working directory.

For the generation of a project file from an OIL file you must at least provide the system's attributes mentioned above. The attributes comprise the OIL file itself, a working directory, a file containing the implementation of all tasks and a resource type model.

INCHRON Tool-Suite's OIL file analysis provides the name of the system's processor. This name is automatically assigned to the resource instance specified in the resource dialog. Only a processor model with OSEK support can be used. Beyond that, the OIL file contains names and attributes of all tasks which are automatically mapped to the resource instance.

The same applies to interrupt service routines defined in the OIL specification file. An interrupt input peripheral component is created for each ISR detected in the OIL file, which will be connected to the ISR automatically. This allows you to instantly start defining stimulation scenarios on the inputs.

All tasks and ISRs must be defined in the task source file, which in turn has to be specified via the Select Task File input.

Additional C source code files can be specified using the Add Files file browser. These files are added to the project and typically contain function and variable declarations and definitions which are employed by the tasks and ISRs. The definition of tasks in added files is not possible. Tasks and ISR definitions have to comply with OSEK notation.

Close the dialog by choosing one of the following three options:

Any project that was generated from an OSEK OIL file can subsequently be used like any other INCHRON project. For example, you can specify additional microcontrollers or add more source code files.

Alternatively to the creation of a new project based on an OIL file it is alternatively possible to update an existing CPU resource from an OIL description.

The undo history is only limited by the computers main memory. The history is not reset on saving a project. On loading a project or creating new project using File → New Project the history will be deleted.

To permanently apply changes to a project it has to be written to disk with File → Save Project .

Invalid or faulty project descriptions can only be removed by manually manipulating elements of your project file. This is done as follows:

The module System presents the hardware and software aspects of the modeled system as well as mapping relations between these. The tree structure on the left show the model's processors as top level elements with assigned peripherals, schedulers, tasks and files as children. Elements may be moved by drag-and-drop mouse operations or copied using the clipboard. When reparenting items, INCHRON Tool-Suite will only accept valid combinations.

By clicking a tree element an editable view of its properties will be shown to the right of the system tree.

Microprocessors are first order elements of an INCHRON project. Further first order elements of an INCHRON project are Event Chains (see Section 6.2.13, “Event Chains”) and RestBus (see Section 6.2.14, “Rest Bus Model”). A microprocessor has the following child elements:

Event Chains appear as top level elements as the result of event chain instrumentation (see Section 6.2.13, “Event Chains”). Customizable settings of an Event Chain are custom step names and instance colors (used in simulation diagrams).

Elements representing peripherals, interrupt service routines, source files, and event chains are grouped by a Container Element. Their purpose is to allow collapsing of elements which are currently not of interest. The container elements are created and removed automatically. Except from grouping they have no functionality, especially there is no property widget associated with them. The source file container element shows the combined status of the contained elements as a hint.

The project element does always exist. To add a child element to any existing tree element do as follows:

The module System's system tree provides common GUI operations: Moving an element (and its children) may be performed by either drag & drop or using the clipboard (copy & paste). For clipboard operations the Edit menu, the Edit toolbar or the usual Ctrl–C and Ctrl–V keyboard combinations may be used.

Please select the root element (project) in the system tree of the System module.

The property view at the right of the system tree shows the project settings and information.

The following global project properties are shown:

The project description may be used for documentation of simulation and analysis results and modification of project settings.

For the working directory it is recommended to use the root directory of the project's source files. In this case INCHRON Tool-Suite will save all file paths as relative path, which alleviates portability to other computers.

It is recommended to save your current work before simulation, analysis or before loading a different project.

Compiler options and preprocessor definitions may be defined globally (on project), on each microprocessor or for each source file. For source file translation all options are concatenated in the following default order: project, microprocessor, source file. This default order may be modified for individual microprocessors and/or source files with a prepend option.

The settings dialog for each level is the same and offers three tabs for Include Path, Preprocessor Definitions and Compiler Options.

Peripheral Components are used to connect the microprocessors of the simulated system with each other and with the environment. The INCHRON Tool-Suite offers a set of predefined library models for them as described in Appendix C, Peripheral Components. These models focus on interaction with the processes by either a register set or a functional API, interrupt request lines (IRQ ports) for triggering interrupt service routines, and input-output ports for connections with other peripherals.

Peripherals come in two different types: buses which can be placed at the project level and controllers which can be placed at the microprocessor level. Currently the following set of peripherals is available:

Some microprocessor models like the nev-v850-pho3 or the m16c60 come with predefined peripherals. These peripherals do appear automatically as children of the microprocessor in the system tree. Additional peripherals may be added at any time during modeling.

To be used in a simulation, each peripheral usually requires the definition of a non-conflicting base address and port connections to other peripherals.

A peripheral is added as follows:

If a peripheral in the system tree is selected its properties are shown on the right. The number and type of the properties depends on the type of peripheral. See Appendix C, Peripheral Components for more information on the peripherals.

For visualization and editing of the connections of input and output ports use the connection editor of Module Architecture. Configuring the association of interrupt ports (named IRQ) with interrupt handlers (ISRs) is available as part of the properites of individual ISRs.

The same source file may be added to multiple microprocessors on project level and show up as individual tree element with individual source file settings. On the other hand, changes to a source file may affect the simulation of different microprocessors if multiple system tree file elements reference the same file.

A source file is added as follows:

If files added to the project are located below the project's working directory (see Section 6.2.4, “Project Information”), Tool-Suite will save relative paths in the project file. This facilitates relocation of INCHRON projects and portability between different computers. Thus it is recommended to always set a project working directory.

Selection of a file element will show its properties and settings. These are the name of the element (which is the source file's path name relative to the project's working directory), the file's Specification Settings and compiler messages resulting from parsing the source file.

In order to assign processes to run on the cores of a microprocessor a scheduler is required. The algorithm to assign CPU time to processes is defined by the scheduler type and strategy.

The DefaultScheduler which is automatically assigned to each microprocessor of an INCHRON Tool-Suite system model contains the processes to be run on the microprocessor.

DefaultScheduler is always child of an ISR-Scheduler which schedules the microprocessor's interrupt service routines. The ISR-Scheduler is priority based so that ISRs will preempt the processes of the DefaultScheduler.

The default type of the DefaultScheduler depends on the chosen operating system.

A scheduler may be added as follows:

Select a scheduler Type to define when scheduling of a process takes place. The type Time-Slice has an additional parameter for the duration of the time slice. With Strategy an algorithm is chosen for the selection of a process to be scheduled.

The Scheduling Properties group box shown in Figure 6.17, “Scheduler Properties” is disabled for a microprocessor's root scheduler (ISR-Scheduler). For a sub-scheduler it shows the same scheduling properties as shown for processes.

The system tree in Figure 6.20, “Process Properties” shows a scheduler with two processes and one sub-scheduler with two more processes. The Processes table in the same figure lists the scheduling parameters of the scheduler's children.

The properties view of a scheduler lists its child processes. The following steps describe adding and configuration of a process. For defining an ISR (Interrupt-Service-Routine) the same steps have to be performed on the ISR-Scheduler of a microprocessor: