Kooperativer Bibliotheksverbund

UID:

Format: 1 Online-Ressource (X, 75 p. 20 illus)

Edition: 1st ed. 2022

ISBN: 9783030963293

Series Statement: SpringerBriefs in Computer Science

Additional Edition: Erscheint auch als Druck-Ausgabe ISBN 978-3-030-96328-6

Additional Edition: Erscheint auch als Druck-Ausgabe ISBN 978-3-030-96330-9

Language: English

DOI: 10.1007/978-3-030-96329-3

URL: Volltext  (URL des Erstveröffentlichers)

UID:

Format: 1 Online-Ressource (XVI, 406 p. 81 illus)

Edition: 3rd ed. 2022

ISBN: 9783031119927

Additional Edition: Erscheint auch als Druck-Ausgabe ISBN 978-3-031-11991-0

Additional Edition: Erscheint auch als Druck-Ausgabe ISBN 978-3-031-11993-4

Additional Edition: Erscheint auch als Druck-Ausgabe ISBN 978-3-031-11994-1

Language: English

DOI: 10.1007/978-3-031-11992-7

URL: Volltext  (URL des Erstveröffentlichers)

UID:

Format: 1 Online-Ressource (x, 148 Seiten) , Illustrationen

ISBN: 9783030204112

Additional Edition: Erscheint auch als Druck-Ausgabe ISBN 978-3-030-20410-5

Additional Edition: Erscheint auch als Druck-Ausgabe ISBN 978-3-030-20412-9

Additional Edition: Erscheint auch als Druck-Ausgabe ISBN 978-3-030-20413-6

Language: English

Subjects: Computer Science

DOI: 10.1007/978-3-030-20411-2

URL: Volltext  (URL des Erstveröffentlichers)

UID:

Format: 1 Online-Ressource

ISBN: 9783319475905 , 9783662503973

Series Statement: Programming and Software Engineering

Content: Computer Systems Organization and Communication Networks; Software Engineering; Complex Systems; Information Systems Applications (incl. Internet); Computer Applications

Note: English

Language: English

URL: kostenfrei

UID:

Format: 1 Online-Ressource (X, 153 Seiten) , Illustrationen, Diagramme

ISBN: 0387230432 , 0387230440 , 9780387230436 , 9780387230443

Series Statement: Real-time systems series 22

Note: Includes bibliographical references (p. [141]-150) and index

Additional Edition: Erscheint auch als Druck-Ausgabe ISBN 978-0-387-23043-6

Language: English

Subjects: Computer Science

Keywords: Echtzeitsystem ; Regelung ; Steuerung ; Computerarchitektur ; Triggerkonzept

DOI: 10.1007/b99995

URL: Volltext

UID:

Format: XVIII, 376 S. , graph. Darst.

Edition: 2. ed.

ISBN: 9781441982377 , 9781441982360

Series Statement: Real-time system series

Note: Lizenzpflichtig

Language: Undetermined

Subjects: Computer Science

Keywords: Echtzeitsystem ; Verifikation ; Echtzeitsystem ; Systemanalyse ; Echtzeitsystem ; Spezifikation

DOI: 10.1007/978-1-4419-8237-7

URN: urn:nbn:de:1111-201104152153

URL: Volltext

URL: https://nbn-resolving.org/urn:nbn:de:1111-201104152153

URL: http://www.springerlink.com/content/978-1-4419-8237-7

UID:

Format: 1 Online-Ressource (XIV, 338 p. 7 illus)

ISBN: 9780306470554

Series Statement: The International Series in Engineering and Computer Science 395

Content: 7. 6 Performance Comparison: ET versus TT. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 164 7. 7 The Physical Layer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 166 Points to Remember . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 168 Bibliographic Notes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 169 Review Questions and Problems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 170 Chapter 8: The Time-Triggered Protocols. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 171 Overview. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Content: . . . . . . . . . . . . . . . . . . . . . . . 171 8. 1 Introduction to Time-Triggered Protocols . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 172 8. 2 Overview of the TTP/C Protocol Layers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 175 8. 3 TheBasic CNI . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 178 Internal Operation of TTP/C . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 181 8. 4 8. 5 TTP/A for Field Bus Applications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 185 Points to Remember. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 188 Bibliographic Notes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Content: . . . . . . . . . . . . . . . . . . 190 Review Questions and Problems. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 190 Chapter 9: Input/Output. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 193 Overview. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 193 9. 1 The Dual Role of Time . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 194 9. 2 Agreement Protocol. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 196 9. 3 Sampling and Polling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 198 9.

Additional Edition: Erscheint auch als Druck-Ausgabe ISBN 9780792398943

Language: English

Subjects: Computer Science

Keywords: Echtzeitsystem ; Systemanalyse ; Echtzeitsystem ; Verifikation ; Echtzeitsystem ; Spezifikation

DOI: 10.1007/b116085

URL: Volltext  (URL des Erstveröffentlichers)

UID:

Format: Online-Ressource , v.: digital

Edition: Online-Ausg. Springer-11645

Edition: Springer eBook Collection. Computer Science

ISBN: 9780306470554

Series Statement: The International Series in Engineering and Computer Science 395

Content: The Real-Time Environment -- Why a Distributed Solution? -- Global Time -- Modeling Real-Time Systems -- Real-Time Entities and Images -- Fault Tolerance -- Real-Time Communication -- The Time-Triggered Protocols -- Input/Output -- Real-Time Operating Systems -- Real-Time Scheduling -- Validation -- System Design -- The Time-Triggered Architecture.

Content: 7. 6 Performance Comparison: ET versus TT. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 164 7. 7 The Physical Layer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 166 Points to Remember . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 168 Bibliographic Notes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 169 Review Questions and Problems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 170 Chapter 8: The Time-Triggered Protocols. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 171 Overview. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 171 8. 1 Introduction to Time-Triggered Protocols . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 172 8. 2 Overview of the TTP/C Protocol Layers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 175 8. 3 TheBasic CNI . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 178 Internal Operation of TTP/C . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 181 8. 4 8. 5 TTP/A for Field Bus Applications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 185 Points to Remember. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 188 Bibliographic Notes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 190 Review Questions and Problems. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 190 Chapter 9: Input/Output. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 193 Overview. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 193 9. 1 The Dual Role of Time . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 194 9. 2 Agreement Protocol. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 196 9. 3 Sampling and Polling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 198 9. 4 Interrupts. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 201 9. 5 Sensors and Actuators . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 203 9. 6 Physical Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 207 Points to Remember. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 208 Bibliographic Notes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 209 Review Questions and Problems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 209 Chapter 10: Real-Time Operating Systems. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 211 Overview. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 211 10. 1 Task Management . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 212 10. 2 Interprocess Communication. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 216 10. 3 Time Management . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 218 10. 4 Error Detection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 219 10. 5 A Case Study: ERCOS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 221 Points to Remember. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 223 Bibliographic Notes. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 224 Review Questions and Problems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 224 Chapter 11: Real-Time Scheduling. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 227 Overview. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 227 11. 1 The Scheduling Problem. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 228 11. 2 The Adversary Argument. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 229 11. 3 Dynamic Scheduling. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 231 x TABLE OF CONTENTS 11. 4 Static Scheduling. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 237 Points to Remember. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 240 Bibliographic Notes. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 242 Review Questions and Problems. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 242 Chapter 12: Validation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 245 Overview. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 245 12. 1 Building aConvincing Safety Case. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 246 12. 2 Formal Methods. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 248 12. 3 Testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Additional Edition: ISBN 9780792398943

Additional Edition: Erscheint auch als Druck-Ausgabe ISBN 9781475770544

Additional Edition: Erscheint auch als Druck-Ausgabe ISBN 9781475770537

Additional Edition: Erscheint auch als Druck-Ausgabe ISBN 9780792398943

Language: English

Keywords: Echtzeitverarbeitung

DOI: 10.1007/b116085

URL: Volltext

URL: lizenzpflichtig

UID:

Format: 1 Online-Ressource(XII, 326 p.)

Edition: 1st ed. 2004.

ISBN: 9781402081491

Series Statement: IFIP Advances in Information and Communication Technology 150

Content: Modelling and Specification -- MDA Platform for Complex Embedded Systems Development -- On Detecting Deadlocks in Large UML Models -- Verification Framework for UML-Based Design of Embedded Systems -- Verification and Analysis -- LTL’s Intuitive Representations and Its Automaton Translation -- Modeling and Verification of Hybrid Systems Based on Equations -- Distribution of Time Interval Between Successive Interrupt Requests -- Fault Detection and Toleration -- A Membership Agreement Algorithm Detecting and Tolerating Asymmetric Timing Faults -- Temporal Bounds for TTA : Validation -- An Active Replication Scheme That Tolerates Failures in Distributed Embedded Real-Time Systems -- Automotive and Mechatronic Systems Design -- Development of Distributed Automotive Software -- Experiences from Model Based Development of Drive-By-Wire Control Systems -- Hardware Design and Protocol Specification for the Control and Communication Within a Mechatronic System -- Networks and Communication -- A Decentralized Self-Organized Approach for Wireless Sensor Networks -- A Software Architecture and Supporting Kernel for Largely Synchronously Operating Sensor Networks -- Adaptive Bus Encoding Schemes for Power-Efficient Data Transfer in DSM Environments -- Scheduling and Resource Management -- A Novel Approach for Off-Line Multiprocessor Scheduling in Embedded Hard Real-Time Systems -- Schedulability Analysis and Design of Real-Time Embedded Systems with Partitions -- Flexible Resource Management -- Hardware Architectures and Synthesis -- Automatic Synthesis of SystemC-Code from Formal Specifications -- Hardware Synthesis of A Parallel JPEG Decoder from Its Functional Specification -- A Self-Controlled and Dynamically Reconfigurable Architecture -- Design Space Exploration -- Profiling Specification Pearl Designs -- A Multiobjective Tabu Search Algorithm for The Design Space Exploration of Embedded Systems -- Design Space Exploration with Automatic Generation of IP-Based Embedded Software -- Design Methodologies and User Interfaces -- A Multi-Level Design Pattern for Embedded Software -- A Petri Net Approach for The Design of Dynamically Modifiable Embedded Systems -- Internet Premium Services for Flexible Format Distributed Devices -- Short Papers -- Evaluating High-Level Models for Real Time Embedded Systems Design -- A Dataflow Language (AVON) as an Architecture Description Language (ADL) -- Engineering Concurrent and Reactive Systems with Distributed Real-Time Abstract State Machines -- The Implications of Real-Time Behavior in Networks-on-Chip Architectures -- ME64 - A Parallel Hardware Architecture for Motion Estimation Implemented in FPGA.

Content: The IFIP TC-10 Working Conference on Distributed and Parallel Embedded Systems (DIPES 2004) brings together experts from industry and academia to discuss recent developments in this important and growing field in the splendid city of Toulouse, France. The ever decreasing price/performance ratio of microcontrollers makes it economically attractive to replace more and more conventional mechanical or electronic control systems within many products by embedded real-time computer systems. An embedded real-time computer system is always part of a well-specified larger system, which we call an intelligent product. Although most intelligent products start out as stand-alone units, many of them are required to interact with other systems at a later stage. At present, many industries are in the middle of this transition from stand-alone products to networked embedded systems. This transition requires reflection and architecting: The complexity of the evolving distributed artifact can only be controlled, if careful planning and principled design methods replace the - hoc engineering of the first version of many standalone embedded products.

Note: Description based upon print version of record , ""Contents""; ""Preface""; ""Conference Committee""; ""1 Modelling and Specification""; ""MDA Platform for Complex Embedded Systems Development""; ""On Detecting Deadlocks in Large UML Models""; ""Verification Framework for UML-Based Design of Embedded Systems""; ""2 Verification and Analysis""; ""LTL�s Intutitive Representations and its Automaton Translation""; ""Modeling and Verification of Hybrid Systems Based on Equations""; ""Distribution of Time Interval Between Successive Interrupt Requests""; ""3 Fault Detection and Toleration"" , ""A Membership Agreement Algorithm Detecting and Tolerating Asymmetric Timing Faults""""Temporal Bounds for TTA: Validation""; ""An Active Replication Scheme that Tolerates Failure in Distributed Embedded Real-Time Systems""; ""4 Automotive and Mechatronic Systems Design""; ""Development of Distributed Automotive Software: The DaVinci Methodology""; ""Experiences from Model Based Development of Drive-By-Wire Control Systems""; ""Hardware Design and Protocol Specification for the Control and Communication within a Mechatronic System""; ""5 Networks and Communication"" , ""A Decentralized Self-Organized Approach for Wireless Sensor Networks""""A Software Architecture and Supporting Kernel for Largely Synchronously Operating Sensor Networks""; ""Adaptive Bus Encoding Schemes for Power-Efficient Data Transfer in DSM Environments""; ""6 Scheduling and Resource Management""; ""A Novel Approach for Off-Line Multiprocesor Scheduling in Embedded Hard Real-Time Systems""; ""Schedulability Analysis and Design of Real-Time Embedded Systems with Partitions""; ""Flexible Resource Management A Framework for Self-Optimizing Real-Time Systems"" , ""7 Hardware Architectures and Synthesis""""Automatic Synthesis of SystemC-Code from Formal Specifications""; ""Hardware Synthesis of a Parallel JPEG Decoder from its Functional Specification""; ""A Self-Controlled and Dynamically Reconfigurable Architecture""; ""8 Design Space Exploration""; ""Profiling Specification PEARL Designs""; ""A Multiobjective Tabu Search Algorithm for the Design Space Exploration of Embedded Systems""; ""Design Space Exploration with Automatic Generation of IP-Based Embedded Software""; ""9 Design Methodologies and User Interfaces"" , ""A Multi-Level Design Pattern for Embedded Software""""A Petri Net Based Approach for the Design of Dynamically Modifiable Embedded Systems""; ""Internet Premium Services for Flexible Format Distributed Services""; ""10 Short Papers""; ""Evaluating High-Level Models for Real-Time Embedded Systems Design""; ""A Dataflow Language (AVON) as an Architecture Description Language (ADL)""; ""Engineering Concurrent and Reactive Systems with Distributed Real-Time Abstract State Machines""; ""The Implications of Real-Time Behavior in Networks-on-Chip Architectures"" , ""ME64 � A Parallel Hardware Architecture for Motion Estimation Implemented in FPGA""

Additional Edition: ISBN 9781475780123

Additional Edition: ISBN 9781402081484

Additional Edition: ISBN 9781475780116

Additional Edition: Erscheint auch als Druck-Ausgabe ISBN 9781475780123

Additional Edition: Erscheint auch als Druck-Ausgabe ISBN 9781402081484

Additional Edition: Erscheint auch als Druck-Ausgabe ISBN 9781475780116

Language: English

Keywords: Eingebettetes System ; Verteiltes System

DOI: 10.1007/b98982

URL: lizenzpflichtig

URL: Volltext

URL: Inhaltstext