Being different from testing for popular GUI software, the “instruction-category” approach is proposed for testing embedded system. This approach is constructed by three steps including refining items, drawing instr...Being different from testing for popular GUI software, the “instruction-category” approach is proposed for testing embedded system. This approach is constructed by three steps including refining items, drawing instruction-brief and instruction-category, and constructing test suite. Consequently, this approach is adopted to test oven embedded system, and detail process is deeply discussed. As a result, the factual result indicates that the “instruction-category” approach can be effectively applied in embedded system testing as a black-box method for conformity testing.展开更多
Taking ARM as the hardware platform, the embedded system is built from both hardware and software aspects with the application as the center. In the hardware design, build the hardware platform scheme, design the sche...Taking ARM as the hardware platform, the embedded system is built from both hardware and software aspects with the application as the center. In the hardware design, build the hardware platform scheme, design the schematic diagram as well as PCB, complete the hardware debugging, and ensure the system hardware platform function;in the software design, optimize the three-stage pipeline structure of ARM instruction system, design the instruction set, install the embedded system on the virtual machine, build the cross-toolchain, and set up the correct NFS network file system. Finish the design of the ARM-based embedded system platform, combined with the hardware requirements of the experimental platform, transplant the powerful Uboot as the Bootloader of the system, and further transplant the Linux-2.6. 32 kernel to the system start the operation normally, and finally, build the root file to finish the study of its portability.展开更多
Aimed at the deficiencies of resources based time Petri nets (RBTPN) in doing scheduling analysis for distributed real-time embedded systems, the assemblage condition of complex scheduling sequences is presented to ...Aimed at the deficiencies of resources based time Petri nets (RBTPN) in doing scheduling analysis for distributed real-time embedded systems, the assemblage condition of complex scheduling sequences is presented to easily compute scheduling length and simplify scheduling analysis. Based on this, a new hierarchical RBTPN model is proposed. The model introduces the definition of transition border set, and represents it as an abstract transition. The abstract transition possesses all resources of the set, and has the highest priority of each resource; the cxecution time of abstract transition is the longest time of all possible scheduling sequences. According to the characteristics and assemblage condition of RBTPN, the refinement conditions of transition border set are given, and the conditions ensure the correction of scheduling analysis. As a result, it is easy for us to understand the scheduling model and perform scheduling analysis.展开更多
Because of limited resource of embedded platforms, the computational complexity of advanced control algorithms raises significant challenges for the use of embedded systems in complex control field. A Scilab/Scicos ba...Because of limited resource of embedded platforms, the computational complexity of advanced control algorithms raises significant challenges for the use of embedded systems in complex control field. A Scilab/Scicos based embedded controller is developed on which various control software can be easily modeled, simulated, implemented, and evaluated to meet the ever-expanding requirements of industrial control applications. Built on the Cirrus Logic EP9315 ARM systems-on-chip board, this embedded controller is possible to develop complex embedded control systems that employ advanced control strategies in a rapid and cost-efficient fashion. Due to the free and open source nature of the software packages used, the cost of the embedded controller is minimized.展开更多
Virtualization has gained great acceptance in the server and cloud computing arena. In recent years, it has also been widely applied to real-time embedded systems with stringent timing constraints. We present a compre...Virtualization has gained great acceptance in the server and cloud computing arena. In recent years, it has also been widely applied to real-time embedded systems with stringent timing constraints. We present a comprehensive survey on real-time issues in virtualization for embedded systems, covering popular virtualization systems including KVM, Xen, L4 and others.展开更多
The formal modelling and verification method has become an effective way of improving the reliability and correctness of complex,safety-critical embedded systems.Statecharts are widely used to formally model embedded ...The formal modelling and verification method has become an effective way of improving the reliability and correctness of complex,safety-critical embedded systems.Statecharts are widely used to formally model embedded applications,but they do not realise the reasonable separation of system concerns,which would result in code scattering and tangling.Aspect-Oriented Software Development(AOSD)technology could separate crosscutting concerns from core concerns and identify potential problems in the early phase of the software development life cycle.Therefore,the paper proposes aspect-oriented timed statecharts(extended timed statecharts with AOSD)to separately model base functional requirements and other requirements(e.g.,scheduling,error handling),thereby improving the modularity and development efficiency of embedded systems.Furthermore,the dynamic behaviours of embedded systems are simulated and analysed to determine whether the model satisfies certain properties(e.g.,liveness,safety)described by computation tree logic formulae.Finally,a given case demonstrates some desired properties processed with respect to the aspect-oriented timed statecharts model.展开更多
This paper treats the problem of designing an optimal size for a lookup table used for sensor linearization. In small embedded systems the lookup table must be reduced to a minimum in order to reduce the memory footpr...This paper treats the problem of designing an optimal size for a lookup table used for sensor linearization. In small embedded systems the lookup table must be reduced to a minimum in order to reduce the memory footprint and intermediate table values are estimated by linear interpolation. Since interpolation introduces an estimation uncertainty that increases with the sparseness of the lookup table there is a trade-off between lookup table size and estimation precision. This work will present a theory for finding the minimum allowed size of a lookup table that does not affect the overall precision, i.e. the overall precision is determined by the lookup table entries’ precision, not by the interpolation error.展开更多
By combining fault-tolerance with power management, this paper developed a new method for aperiodic task set for the problem of task scheduling and voltage allocation in embedded real-time systems. The scbedulability ...By combining fault-tolerance with power management, this paper developed a new method for aperiodic task set for the problem of task scheduling and voltage allocation in embedded real-time systems. The scbedulability of the system was analyzed through checkpointing and the energy saving was considered via dynamic voltage and frequency scaling. Simulation results showed that the proposed algorithm had better performance compared with the existing voltage allocation techniques. The proposed technique saves 51.5% energy over FT-Only and 19.9% over FT + EC on average. Therefore, the proposed method was more appropriate for aperiodic tasks in embedded real-time systems.展开更多
In the traditional project of industry control, the field operator is the only man who watches production condition at the production spot. Enterprise administers cannot obtain real-time production status and make rea...In the traditional project of industry control, the field operator is the only man who watches production condition at the production spot. Enterprise administers cannot obtain real-time production status and make real-time decision if they don’t reach the production spot. Because of the development of Embedded Web Server such status is being changed. The remote monitor and control mode based on Embedded Web Server provides complete exact real-time information for managers, and makes it possible to make a decision in real time. In the paper, the design and implements of Embedded Web Server are presented and the key realization technology of it is described in detail. EWS (Embedded Web Server) will effectively lower system operating cost and improve maintaining efficiency, which has wide application prospect and popularization value in industrial control systems.展开更多
Design Patterns, which give abstract solutions to commonly recurring design problems, have been widely used in the software and hardware domain. As non-functional requirements are an important aspect in the design of ...Design Patterns, which give abstract solutions to commonly recurring design problems, have been widely used in the software and hardware domain. As non-functional requirements are an important aspect in the design of safety-critical embedded systems, this work focuses on the integration of non-functional implications in an existing design pattern concept. We propose a pattern representation for safety-critical embedded application design methods by including fields for the implications and side effects of the represented design pattern on the non-functional requirements of the overall systems. The considered requirements include safety, reliability, modifiability, cost, and execution time.展开更多
This paper presents the development of a microkernel with a device driver controller for embedded systems. The implementation was done in C language aiming low cost microcontrollers. The proposed system allowed to per...This paper presents the development of a microkernel with a device driver controller for embedded systems. The implementation was done in C language aiming low cost microcontrollers. The proposed system allowed to perform soft real-time activities while keeping the drivers and the application isolated by a secure layer. The callback system proved itself extremely simple to use while still maintaining the security of the system regarding the temporal constraints.展开更多
Today, the number of embedded system was applied in the field of automation and control has far exceeded a variety of general-purpose computer. Embedded system is gradually penetrated into all fields of human society,...Today, the number of embedded system was applied in the field of automation and control has far exceeded a variety of general-purpose computer. Embedded system is gradually penetrated into all fields of human society, and ubiquitous embedded applications constitute the 'ubiquitous' computing era. Embedded operating system is the core of the em-bedded system, and it directly affects the performance of the whole system. Our Liaoning Provincial Key Laboratory of Embedded Technology has successfully developed five kinds of device-level embedded operating systems by more than ten years’ efforts, and these systems are Webit 5.0, Worix, μKernel, iDCX 128 and μc/os-II 128. This paper mainly analyses and compares the implementation mechanism and performance of these five kinds of device-level embedded operating systems in detail.展开更多
In this study, we present a miniOS kernel implemented via analysis of the context switching, the scheduler, and the memory management of the original OS kernel for an embedded system based on ARM core. Since this is a...In this study, we present a miniOS kernel implemented via analysis of the context switching, the scheduler, and the memory management of the original OS kernel for an embedded system based on ARM core. Since this is a large subject, we have limited our scope to them only that made up an embedded operating system. The implemented miniOS kernel is composed only by them, to the exclusion of all other functions of the original kernel. Our goal is to modify the OS kernel depending on the product function. The implementation method of the miniOS kernel can be applicable to any OS being mounted based on the ARM core. Modifying the kernel depending on the product function can improve the OS booting speed as well as save the system memory. The functions of the scheduler, the context switching, and the memory management are described with the source in each section. The miniOS kernel was implemented in the Assembly and C language and was verified through the build and the test. The results are shown in the Section 5.展开更多
The choice of methods or design languages is a crucial phase in the development of systems and software, also for real time and embedded systems. An open question that remains in the design of these types of systems i...The choice of methods or design languages is a crucial phase in the development of systems and software, also for real time and embedded systems. An open question that remains in the design of these types of systems is to build a method, or to choose one among those existing, capable to cover the life cycle of a project, and particularly the development phases. This article contributes to answer the question, by proposing an approach based on a multi-criteria comparative study, of few languages and methods dedicated to the design of real time and embedded systems. The underlying objective of this work is to present to designers a wide range of approaches, and elements that can guide their choices. In order to reach this goal, we propose different comparison criteria. Each criterion is divided into sub-criteria, so that the designers can refine their choices according to the qualities they prefer and wish to have in the method or language. We also define a rating scale which is used to assess the retained languages and methods. The scores obtained from this assessment are presented in tables, one table per criterion, followed by a summary table giving the overall scores. Graphics built from these tables are provided and intend to facilitate the judgement and thus the choice of the designers.展开更多
The parameter embedding method is applied for numerically solving the perturbed conservative systems. By means of Newtonian iteration, a simple algorithm has been constructed. Finally, the convergence of the iteration...The parameter embedding method is applied for numerically solving the perturbed conservative systems. By means of Newtonian iteration, a simple algorithm has been constructed. Finally, the convergence of the iteration is proved.展开更多
This paper introduces the architecture and components of LXI instrument development platform based on an open embedded operating system,which is a modular and configurable platform.The platform is a total solution to ...This paper introduces the architecture and components of LXI instrument development platform based on an open embedded operating system,which is a modular and configurable platform.The platform is a total solution to develop LXI instrument modules and systems.On the other hand,it also supports other types of instrument development.This is a generic and efficient platform.At the end,this paper addresses the technical tends, challenges,and recormnends solutions.展开更多
A platform named EMECS based on embedded Ethernet control system is implemented.A PC running Fedora 6(Linux2.6)works as a central controller.A kit running Linux 2.4 based on Samsung2410A(ARM920t core)works as a remote...A platform named EMECS based on embedded Ethernet control system is implemented.A PC running Fedora 6(Linux2.6)works as a central controller.A kit running Linux 2.4 based on Samsung2410A(ARM920t core)works as a remote controller and a DC motor(ESCA P28HSL18-219/204)made by Portescap Company works as a plant.Firstly,system modeling is presented by analyzing the characteristics of Ethernet and the plant,based on a proposed delay measurement method.Secondly,implementation of the system including program and hardware is described in detail.And then the delay is measured and the control results of the system are tested in three cases with different network loads as well.The platform is proved to have flexibility of running different control algorithms and extensibility of adding nodes.Experiment results demonstrate the validity of the system.展开更多
The software-based computer numerical control(CNC) system includes three types of tasks: periodic real-time tasks, aperiodic real-time tasks, and non-real-time tasks. The tasks are characterized by concurrency, hyb...The software-based computer numerical control(CNC) system includes three types of tasks: periodic real-time tasks, aperiodic real-time tasks, and non-real-time tasks. The tasks are characterized by concurrency, hybridization, and correlation, which make system implementation difficult. The conventional scheduling algorithm can not meet the demands of system implementation in the software-based CNC system completely. The uncertainty factors when running real-time tasks affect control performance by degrading manufacturing accuracy as a result of system resource and processor use restrictions. To address the technical difficulty of embedded system implementation, a novel fuzzy feedback scheduling algorithm based on output jitter of key real-time tasks for a software-based CNC system is proposed. Time characteristics, such as sampling jitter, input-output jitter, and non-schedulability are discussed, followed by quantification through simulations of the impact of time characteristics on manufacturing accuracy. On the basis of this research, the scheduler architecture is designed, and then the algorithm table is calculated. When the system resource changes, the key periodic real-time tasks meet their deadlines by means of dynamically adjusting the task period. The simulated results show that the machining precision rises by an order of magnitude for the proposed scheduler in resource-constrained software-based CNC systems. Moreover, unlike conventional feedback scheduling methods, the algorithm in this paper does not rely on the availability of task execution times and is easy to implement while incurring only a small overhead.展开更多
文摘Being different from testing for popular GUI software, the “instruction-category” approach is proposed for testing embedded system. This approach is constructed by three steps including refining items, drawing instruction-brief and instruction-category, and constructing test suite. Consequently, this approach is adopted to test oven embedded system, and detail process is deeply discussed. As a result, the factual result indicates that the “instruction-category” approach can be effectively applied in embedded system testing as a black-box method for conformity testing.
文摘Taking ARM as the hardware platform, the embedded system is built from both hardware and software aspects with the application as the center. In the hardware design, build the hardware platform scheme, design the schematic diagram as well as PCB, complete the hardware debugging, and ensure the system hardware platform function;in the software design, optimize the three-stage pipeline structure of ARM instruction system, design the instruction set, install the embedded system on the virtual machine, build the cross-toolchain, and set up the correct NFS network file system. Finish the design of the ARM-based embedded system platform, combined with the hardware requirements of the experimental platform, transplant the powerful Uboot as the Bootloader of the system, and further transplant the Linux-2.6. 32 kernel to the system start the operation normally, and finally, build the root file to finish the study of its portability.
文摘Aimed at the deficiencies of resources based time Petri nets (RBTPN) in doing scheduling analysis for distributed real-time embedded systems, the assemblage condition of complex scheduling sequences is presented to easily compute scheduling length and simplify scheduling analysis. Based on this, a new hierarchical RBTPN model is proposed. The model introduces the definition of transition border set, and represents it as an abstract transition. The abstract transition possesses all resources of the set, and has the highest priority of each resource; the cxecution time of abstract transition is the longest time of all possible scheduling sequences. According to the characteristics and assemblage condition of RBTPN, the refinement conditions of transition border set are given, and the conditions ensure the correction of scheduling analysis. As a result, it is easy for us to understand the scheduling model and perform scheduling analysis.
基金supported in part by the National Natural Science Foundation under Grant No.61070003,No.61272020,and No.61071128Zhejiang Provincial Natural Science Foundation under Grant No.R1090052 and No.Y1101184
文摘Because of limited resource of embedded platforms, the computational complexity of advanced control algorithms raises significant challenges for the use of embedded systems in complex control field. A Scilab/Scicos based embedded controller is developed on which various control software can be easily modeled, simulated, implemented, and evaluated to meet the ever-expanding requirements of industrial control applications. Built on the Cirrus Logic EP9315 ARM systems-on-chip board, this embedded controller is possible to develop complex embedded control systems that employ advanced control strategies in a rapid and cost-efficient fashion. Due to the free and open source nature of the software packages used, the cost of the embedded controller is minimized.
文摘Virtualization has gained great acceptance in the server and cloud computing arena. In recent years, it has also been widely applied to real-time embedded systems with stringent timing constraints. We present a comprehensive survey on real-time issues in virtualization for embedded systems, covering popular virtualization systems including KVM, Xen, L4 and others.
基金supported by the National Natural Science Foundation of China under GrantsNo.61173048,No.61103115
文摘The formal modelling and verification method has become an effective way of improving the reliability and correctness of complex,safety-critical embedded systems.Statecharts are widely used to formally model embedded applications,but they do not realise the reasonable separation of system concerns,which would result in code scattering and tangling.Aspect-Oriented Software Development(AOSD)technology could separate crosscutting concerns from core concerns and identify potential problems in the early phase of the software development life cycle.Therefore,the paper proposes aspect-oriented timed statecharts(extended timed statecharts with AOSD)to separately model base functional requirements and other requirements(e.g.,scheduling,error handling),thereby improving the modularity and development efficiency of embedded systems.Furthermore,the dynamic behaviours of embedded systems are simulated and analysed to determine whether the model satisfies certain properties(e.g.,liveness,safety)described by computation tree logic formulae.Finally,a given case demonstrates some desired properties processed with respect to the aspect-oriented timed statecharts model.
文摘This paper treats the problem of designing an optimal size for a lookup table used for sensor linearization. In small embedded systems the lookup table must be reduced to a minimum in order to reduce the memory footprint and intermediate table values are estimated by linear interpolation. Since interpolation introduces an estimation uncertainty that increases with the sparseness of the lookup table there is a trade-off between lookup table size and estimation precision. This work will present a theory for finding the minimum allowed size of a lookup table that does not affect the overall precision, i.e. the overall precision is determined by the lookup table entries’ precision, not by the interpolation error.
基金The National Natural Science Foundationof China(No.60873030 )the National High-Tech Research and Development Plan of China(863 Program)(No.2007AA01Z309)
文摘By combining fault-tolerance with power management, this paper developed a new method for aperiodic task set for the problem of task scheduling and voltage allocation in embedded real-time systems. The scbedulability of the system was analyzed through checkpointing and the energy saving was considered via dynamic voltage and frequency scaling. Simulation results showed that the proposed algorithm had better performance compared with the existing voltage allocation techniques. The proposed technique saves 51.5% energy over FT-Only and 19.9% over FT + EC on average. Therefore, the proposed method was more appropriate for aperiodic tasks in embedded real-time systems.
文摘In the traditional project of industry control, the field operator is the only man who watches production condition at the production spot. Enterprise administers cannot obtain real-time production status and make real-time decision if they don’t reach the production spot. Because of the development of Embedded Web Server such status is being changed. The remote monitor and control mode based on Embedded Web Server provides complete exact real-time information for managers, and makes it possible to make a decision in real time. In the paper, the design and implements of Embedded Web Server are presented and the key realization technology of it is described in detail. EWS (Embedded Web Server) will effectively lower system operating cost and improve maintaining efficiency, which has wide application prospect and popularization value in industrial control systems.
文摘Design Patterns, which give abstract solutions to commonly recurring design problems, have been widely used in the software and hardware domain. As non-functional requirements are an important aspect in the design of safety-critical embedded systems, this work focuses on the integration of non-functional implications in an existing design pattern concept. We propose a pattern representation for safety-critical embedded application design methods by including fields for the implications and side effects of the represented design pattern on the non-functional requirements of the overall systems. The considered requirements include safety, reliability, modifiability, cost, and execution time.
文摘This paper presents the development of a microkernel with a device driver controller for embedded systems. The implementation was done in C language aiming low cost microcontrollers. The proposed system allowed to perform soft real-time activities while keeping the drivers and the application isolated by a secure layer. The callback system proved itself extremely simple to use while still maintaining the security of the system regarding the temporal constraints.
文摘Today, the number of embedded system was applied in the field of automation and control has far exceeded a variety of general-purpose computer. Embedded system is gradually penetrated into all fields of human society, and ubiquitous embedded applications constitute the 'ubiquitous' computing era. Embedded operating system is the core of the em-bedded system, and it directly affects the performance of the whole system. Our Liaoning Provincial Key Laboratory of Embedded Technology has successfully developed five kinds of device-level embedded operating systems by more than ten years’ efforts, and these systems are Webit 5.0, Worix, μKernel, iDCX 128 and μc/os-II 128. This paper mainly analyses and compares the implementation mechanism and performance of these five kinds of device-level embedded operating systems in detail.
文摘In this study, we present a miniOS kernel implemented via analysis of the context switching, the scheduler, and the memory management of the original OS kernel for an embedded system based on ARM core. Since this is a large subject, we have limited our scope to them only that made up an embedded operating system. The implemented miniOS kernel is composed only by them, to the exclusion of all other functions of the original kernel. Our goal is to modify the OS kernel depending on the product function. The implementation method of the miniOS kernel can be applicable to any OS being mounted based on the ARM core. Modifying the kernel depending on the product function can improve the OS booting speed as well as save the system memory. The functions of the scheduler, the context switching, and the memory management are described with the source in each section. The miniOS kernel was implemented in the Assembly and C language and was verified through the build and the test. The results are shown in the Section 5.
文摘The choice of methods or design languages is a crucial phase in the development of systems and software, also for real time and embedded systems. An open question that remains in the design of these types of systems is to build a method, or to choose one among those existing, capable to cover the life cycle of a project, and particularly the development phases. This article contributes to answer the question, by proposing an approach based on a multi-criteria comparative study, of few languages and methods dedicated to the design of real time and embedded systems. The underlying objective of this work is to present to designers a wide range of approaches, and elements that can guide their choices. In order to reach this goal, we propose different comparison criteria. Each criterion is divided into sub-criteria, so that the designers can refine their choices according to the qualities they prefer and wish to have in the method or language. We also define a rating scale which is used to assess the retained languages and methods. The scores obtained from this assessment are presented in tables, one table per criterion, followed by a summary table giving the overall scores. Graphics built from these tables are provided and intend to facilitate the judgement and thus the choice of the designers.
文摘The parameter embedding method is applied for numerically solving the perturbed conservative systems. By means of Newtonian iteration, a simple algorithm has been constructed. Finally, the convergence of the iteration is proved.
文摘This paper introduces the architecture and components of LXI instrument development platform based on an open embedded operating system,which is a modular and configurable platform.The platform is a total solution to develop LXI instrument modules and systems.On the other hand,it also supports other types of instrument development.This is a generic and efficient platform.At the end,this paper addresses the technical tends, challenges,and recormnends solutions.
基金Supported by CSC(Chinese Scholarship)(Liu Jin Chu[2006]3074)
文摘A platform named EMECS based on embedded Ethernet control system is implemented.A PC running Fedora 6(Linux2.6)works as a central controller.A kit running Linux 2.4 based on Samsung2410A(ARM920t core)works as a remote controller and a DC motor(ESCA P28HSL18-219/204)made by Portescap Company works as a plant.Firstly,system modeling is presented by analyzing the characteristics of Ethernet and the plant,based on a proposed delay measurement method.Secondly,implementation of the system including program and hardware is described in detail.And then the delay is measured and the control results of the system are tested in three cases with different network loads as well.The platform is proved to have flexibility of running different control algorithms and extensibility of adding nodes.Experiment results demonstrate the validity of the system.
基金supported by National Natural Science Foundation of China(Grant No.50875090,Grant No.50905063)National Hi-tech Research and Development Program of China(863 Program,Grant No.2009AA4Z111)China Postdoctoral Science Foundation (Grant No.20090460769)
文摘The software-based computer numerical control(CNC) system includes three types of tasks: periodic real-time tasks, aperiodic real-time tasks, and non-real-time tasks. The tasks are characterized by concurrency, hybridization, and correlation, which make system implementation difficult. The conventional scheduling algorithm can not meet the demands of system implementation in the software-based CNC system completely. The uncertainty factors when running real-time tasks affect control performance by degrading manufacturing accuracy as a result of system resource and processor use restrictions. To address the technical difficulty of embedded system implementation, a novel fuzzy feedback scheduling algorithm based on output jitter of key real-time tasks for a software-based CNC system is proposed. Time characteristics, such as sampling jitter, input-output jitter, and non-schedulability are discussed, followed by quantification through simulations of the impact of time characteristics on manufacturing accuracy. On the basis of this research, the scheduler architecture is designed, and then the algorithm table is calculated. When the system resource changes, the key periodic real-time tasks meet their deadlines by means of dynamically adjusting the task period. The simulated results show that the machining precision rises by an order of magnitude for the proposed scheduler in resource-constrained software-based CNC systems. Moreover, unlike conventional feedback scheduling methods, the algorithm in this paper does not rely on the availability of task execution times and is easy to implement while incurring only a small overhead.