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Aittamaa, Simon
Publications (9 of 9) Show all publications
Eriksson, J., Häggström, F., Aittamaa, S., Kruglyak, A. & Lindgren, P. (2013). Real-time for the masses: Step 1: programming API and static priority SRP kernel primitives (ed.). In: (Ed.), (Ed.), 2013 8th IEEE International Symposium on Industrial and Embedded Systems (SIES 2013): 19-21 June 2013, Porto, Portugal. Paper presented at IEEE International Symposium on Industrial Embedded Systems : 19/06/2013 - 21/06/2013 (pp. 110-113). Piscataway, NJ: IEEE Communications Society
Open this publication in new window or tab >>Real-time for the masses: Step 1: programming API and static priority SRP kernel primitives
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2013 (English)In: 2013 8th IEEE International Symposium on Industrial and Embedded Systems (SIES 2013): 19-21 June 2013, Porto, Portugal, Piscataway, NJ: IEEE Communications Society, 2013, p. 110-113Conference paper, Published paper (Refereed)
Abstract [en]

Lightweight Real-Time Operating Systems have gained widespread use in implementing embedded software on lightweight nodes. However, bare metal solutions are chosen, e.g., when the reactive (interrupt-driven) paradigm better matches the programmer’s intent, when the OS features are not needed, or when the OS overhead is deemed too large. Moreover, other approaches are used when real-time guarantees are required. Establishing real-time and resource guarantees typically requires expert knowledge in the field, as no turn-key solutions are available to the masses.In this paper we set out to bridge the gap between bare metal solutions and traditional Real-Time OS paradigms. Our goal is to meet the intuition of the programmer and at the same time provide a resource-efficient (w.r.t. CPU and memory) implementation with established properties, such as bounded memory usage and guaranteed response times. We outline a roadmap for Real-Time For the Masses (RTFM) and report on the first step: an intuitive, platform-independent programming API backed by an efficient Stack Resource Policy-based scheduler and a tool for kernel configuration and basic resource and timing analysis.

Place, publisher, year, edition, pages
Piscataway, NJ: IEEE Communications Society, 2013
Keywords
Information technology - Systems engineering, Informationsteknik - Systemteknik
National Category
Embedded Systems Other Electrical Engineering, Electronic Engineering, Information Engineering
Research subject
Embedded System; Industrial Electronics
Identifiers
urn:nbn:se:ltu:diva-32446 (URN)10.1109/SIES.2013.6601482 (DOI)2-s2.0-84885398239 (Scopus ID)6f199cd4-5aa4-4696-a750-baf5affeca89 (Local ID)6f199cd4-5aa4-4696-a750-baf5affeca89 (Archive number)6f199cd4-5aa4-4696-a750-baf5affeca89 (OAI)
Conference
IEEE International Symposium on Industrial Embedded Systems : 19/06/2013 - 21/06/2013
Projects
ESIS
Note
Godkänd; 2013; 20130701 (pln)Available from: 2016-09-30 Created: 2016-09-30 Last updated: 2018-07-10Bibliographically approved
Aittamaa, S. (2011). Programming embedded real-time systems: implementation techniques for concurrent reactive objects (ed.). (Licentiate dissertation). Paper presented at . Luleå: Luleå tekniska universitet
Open this publication in new window or tab >>Programming embedded real-time systems: implementation techniques for concurrent reactive objects
2011 (English)Licentiate thesis, comprehensive summary (Other academic)
Abstract [en]

An embedded system is a computer system that is a part of a larger device with hardware and mechanical parts. Such a system often has limited resources (such as processing power, memory, and power) and it typically has to meet hard real-time requirements. Today, as the area of application of embedded systems is constantly increasing, resulting in higher demands on system performance and a growing complexity of embedded software, there is a clear trend towards multi-core and multi-processor systems. Such systems are inherently concurrent, but programming concurrent systems using the traditional abstractions (i.e., explicit threads of execution) has been shown to be both difficult and error-prone. The natural solution is to raise the abstraction level and make concurrency implicit, in order to aid the programmer in the task of writing correct code. However, when we raise the abstraction level, there is always an inherent cost. In this thesis we consider one possible concurrency model, the concurrent reactive object approach that offers implicit concurrency at the object level. This model has been implemented in the programming language Timber, which primarily targets development of real-time systems. It is also implemented in TinyTimber, a subset of the C language closely matching Timber’s execution model. We quantify various costs of a TinyTimber implementation of the model (such as context switching and message passing overheads) on a number of hardware platforms and compare them to the costs of the more common thread-based approach. We then demonstrate how some of these costs can be mitigated using stack resource policy. On a separate track, we present a feasibility test for garbage collection in a reactive real-time system with automatic memory management, which is a necessary component for verification of correctness of a real-time system implemented in Timber

Place, publisher, year, edition, pages
Luleå: Luleå tekniska universitet, 2011
Series
Licentiate thesis / Luleå University of Technology, ISSN 1402-1757
National Category
Embedded Systems
Research subject
Embedded System
Identifiers
urn:nbn:se:ltu:diva-18171 (URN)7427cde0-f70f-11df-8b95-000ea68e967b (Local ID)978-91-7439-194-7 (ISBN)7427cde0-f70f-11df-8b95-000ea68e967b (Archive number)7427cde0-f70f-11df-8b95-000ea68e967b (OAI)
Note
Godkänd; 2011; 20101123 (simait); LICENTIATSEMINARIUM Ämnesområde: Inbyggda system/Embedded Systems Examinator: Professor Per Lindgren, Institutionen för system- och rymdteknik, Luleå tekniska universitet Diskutant: Professor Mikael Sjödin, Mälardalens högskola, Västerås/Eskilstuna Tid: Måndag den 23 maj 2011 kl 13.00 Plats: A1514 - Demostudion, Luleå tekniska universitetAvailable from: 2016-09-29 Created: 2016-09-29 Last updated: 2017-11-24Bibliographically approved
Lindgren, P., Eriksson, J., Aittamaa, S., Pietrzak, P. & Wiklander, J. (2011). Scheduling of CRO systems under SPR-DM (ed.). Paper presented at Real-Time in Sweden : 13/06/2011 - 14/06/2011. Paper presented at Real-Time in Sweden : 13/06/2011 - 14/06/2011.
Open this publication in new window or tab >>Scheduling of CRO systems under SPR-DM
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2011 (English)Conference paper, Oral presentation only (Refereed)
National Category
Embedded Systems
Research subject
Embedded System
Identifiers
urn:nbn:se:ltu:diva-35388 (URN)9e7d8669-d562-48f9-8742-f972866fdfca (Local ID)9e7d8669-d562-48f9-8742-f972866fdfca (Archive number)9e7d8669-d562-48f9-8742-f972866fdfca (OAI)
Conference
Real-Time in Sweden : 13/06/2011 - 14/06/2011
Note
Godkänd; 2011; 20111122 (ysko)Available from: 2016-09-30 Created: 2016-09-30 Last updated: 2017-11-25Bibliographically approved
Eriksson, J., Aittamaa, S., Wiklander, J., Pietrzak, P. & Lindgren, P. (2011). SRP-DM scheduling of component-based embedded real-time software (ed.). Paper presented at International Workshop on Dependable and Secure Industrial and Embedded Systems : 04/06/2011 - 04/06/2011. Paper presented at International Workshop on Dependable and Secure Industrial and Embedded Systems : 04/06/2011 - 04/06/2011.
Open this publication in new window or tab >>SRP-DM scheduling of component-based embedded real-time software
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2011 (English)Conference paper, Oral presentation only (Refereed)
Abstract [en]

Model and component based design is an established means for the development of large software systems, and is starting to get momentum in the realm of embedded software development. In case of safety critical (dependable systems) it is crucial that the underlying model and its realization captures the requirements on the timely behavior of the system, and that these requirements can be preserved and validated throughout the design process (from specification to actual code execution). To this end, we base the presented work on the notion of Concurrent Reactive Objects (CRO) and their abstraction into Reactive Components.In many cases, the execution platform puts firm resource limitations on available memory and speed of computations that must be taken into consideration for the validation of the system.In this paper, we focus on code synthesis from the model, and we show how specified timing requirements are preserved and translated into scheduling information. In particular, we present how ceiling levels for Stack Resources Policy (SRP) scheduling and analysis can be extracted from the model. Additionally, to support schedulability analysis, we detail algorithms that for a CRO model derives periods (minimum inter-arrival times) and offsets of tasks/jobs. Moreover, the design of a micro-kernel supporting cooperative hardware- and software-scheduling of CRO based systems under Deadline Monotonic SRP is presented.

National Category
Embedded Systems
Research subject
Embedded System
Identifiers
urn:nbn:se:ltu:diva-34558 (URN)8c7a9196-a0ce-4944-83da-07d3add16d5f (Local ID)8c7a9196-a0ce-4944-83da-07d3add16d5f (Archive number)8c7a9196-a0ce-4944-83da-07d3add16d5f (OAI)
Conference
International Workshop on Dependable and Secure Industrial and Embedded Systems : 04/06/2011 - 04/06/2011
Note
Godkänd; 2011; 20111215 (andbra)Available from: 2016-09-30 Created: 2016-09-30 Last updated: 2017-11-25Bibliographically approved
Kero, M. & Aittamaa, S. (2010). Scheduling garbage collection in realtime systems (ed.). In: (Ed.), (Ed.), CODES/ISSS '10 Proceedings of the eighth IEEE/ACM/IFIP international conference on Hardware/software codesign and system synthesis: . Paper presented at International Conference on Hardware-Software Codesign and System Synthesis : 24/10/2010 - 29/10/2010 (pp. 51-60). New York, NY: ACM Digital Library
Open this publication in new window or tab >>Scheduling garbage collection in realtime systems
2010 (English)In: CODES/ISSS '10 Proceedings of the eighth IEEE/ACM/IFIP international conference on Hardware/software codesign and system synthesis, New York, NY: ACM Digital Library, 2010, p. 51-60Conference paper, Published paper (Refereed)
Abstract [en]

The key to successful deployment of garbage collection in real-time systems is to enable provably safe schedulability tests of the real-time tasks. At the same time one must be able to determine the total heap usage of the system. Schedulability tests typically require a uniformed model of timing assumptions (inter-arrival times, deadlines, etc.). Incorporating the cost of garbage collection in such tests typically requires both artificial timing assumptions of the garbage collector and restricted capabilities of the task scheduler. In this paper, we pursue a different approach. We show how the reactive object model of the programming language Timber enables us to decouple the cost of a concurrently running copying garbage collector from the schedulability of the real-time tasks. I.e., we enable any regular schedulability analysis without the need of incorporating the cost of an interfering garbage collector. We present the garbage collection demand analysis, which determines if the garbage collector can be feasibly scheduled in the system.

Place, publisher, year, edition, pages
New York, NY: ACM Digital Library, 2010
National Category
Embedded Systems
Research subject
Embedded System
Identifiers
urn:nbn:se:ltu:diva-28516 (URN)10.1145/1878961.1878971 (DOI)2-s2.0-78650669388 (Scopus ID)255107c0-c1ab-11df-a707-000ea68e967b (Local ID)978-1-60558-905-3 (ISBN)255107c0-c1ab-11df-a707-000ea68e967b (Archive number)255107c0-c1ab-11df-a707-000ea68e967b (OAI)
Conference
International Conference on Hardware-Software Codesign and System Synthesis : 24/10/2010 - 29/10/2010
Note
Godkänd; 2010; 20100916 (keero)Available from: 2016-09-30 Created: 2016-09-30 Last updated: 2018-07-10Bibliographically approved
Aittamaa, S., Eriksson, J. & Lindgren, P. (2010). Uniform scheduling of internal and external events under SRP-EDF (ed.). In: (Ed.), (Ed.), Annual International Conference on Real-Time and Embedded Systems ( RTES 2010): 1-2 November 2010, Mandarin Orchard Hotel, Singapore. Paper presented at International Conference on Real-Time and Embedded Systems : 01/11/2010 - 02/11/2010.
Open this publication in new window or tab >>Uniform scheduling of internal and external events under SRP-EDF
2010 (English)In: Annual International Conference on Real-Time and Embedded Systems ( RTES 2010): 1-2 November 2010, Mandarin Orchard Hotel, Singapore, 2010Conference paper, Published paper (Refereed)
Abstract [en]

With the growing complexity of modern embedded real-time systems, scheduling and managing of resources has become a daunting task. While scheduling and resource management for internal events can be simplified by adopting a commonplace real-time operating system (RTOS), scheduling and resource management for external events are left in the hands of the programmer, not to mention managing resources across the boundaries of external and internal events. In this paper we propose a unified system view incorporating earliest deadline first (EDF) for scheduling and stack resource policy (SRP) for resource management. From an embedded real-time system view, EDF+SRP is attractive not only because stack usage can be minimized, but also because the cost of a pre-emption becomes almost as cheap as a regular function call, and the number of preemptions is kept to a minimum. SRP+EDF also lifts the burden of manual resource management from the programmer and incorporates it into the scheduler. Furthermore, we show the efficiency of the SRP+EDF scheme, the intuitiveness of the programming model (in terms of reactive programming), and the simplicity of the implementation.

National Category
Embedded Systems
Research subject
Embedded System
Identifiers
urn:nbn:se:ltu:diva-39049 (URN)da3eacd0-f727-11df-8b95-000ea68e967b (Local ID)da3eacd0-f727-11df-8b95-000ea68e967b (Archive number)da3eacd0-f727-11df-8b95-000ea68e967b (OAI)
Conference
International Conference on Real-Time and Embedded Systems : 01/11/2010 - 02/11/2010
Note
Godkänd; 2010; 20101123 (simait)Available from: 2016-10-03 Created: 2016-10-03 Last updated: 2017-11-25Bibliographically approved
Lindgren, P., Nordlander, J., Hyyppä, K., Aittamaa, S. & Eriksson, J. (2008). Comprehensive reactive real-time programming (ed.). In: (Ed.), (Ed.), Hawaii International Conference on Education: 2008 Conference Proceedings. Paper presented at Annual Hawaii International Conference on Education, 2008 : 05/01/2008 - 08/01/2008 (pp. 1440-1448).
Open this publication in new window or tab >>Comprehensive reactive real-time programming
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2008 (English)In: Hawaii International Conference on Education: 2008 Conference Proceedings, 2008, p. 1440-1448Conference paper, Published paper (Refereed)
National Category
Embedded Systems Computer Sciences Other Electrical Engineering, Electronic Engineering, Information Engineering
Research subject
Embedded System; Dependable Communication and Computation Systems; Industrial Electronics
Identifiers
urn:nbn:se:ltu:diva-31867 (URN)62d92b20-7336-11dc-86ab-000ea68e967b (Local ID)62d92b20-7336-11dc-86ab-000ea68e967b (Archive number)62d92b20-7336-11dc-86ab-000ea68e967b (OAI)
Conference
Annual Hawaii International Conference on Education, 2008 : 05/01/2008 - 08/01/2008
Projects
CASTT - Centre for Automotive Systems Technologies and Testing
Note
Godkänd; 2008; 20071005 (pln)Available from: 2016-09-30 Created: 2016-09-30 Last updated: 2018-01-14Bibliographically approved
Lindgren, P., Aittamaa, S. & Eriksson, J. (2008). IP over CAN: transparent vehicular to infrastructure access (ed.). In: (Ed.), (Ed.), 2008 Consumer Communications and Networking Conference: [IEEE CCNC 2008] ; Las Vegas, Nevada, 10 - 12 January 2008. Paper presented at IEEE Consumer Communications and Networking Conference : 10/01/2008 - 12/01/2008 (pp. 758-759). Piscataway, NJ: IEEE Communications Society
Open this publication in new window or tab >>IP over CAN: transparent vehicular to infrastructure access
2008 (English)In: 2008 Consumer Communications and Networking Conference: [IEEE CCNC 2008] ; Las Vegas, Nevada, 10 - 12 January 2008, Piscataway, NJ: IEEE Communications Society, 2008, p. 758-759Conference paper, Published paper (Refereed)
Abstract [en]

For the future we foresee each vehicle to feature wireless communication (to the Internet and/or other vehicles) over various technologies, e.g., UMTS/GPRS, and WLAN/WiFi. In this paper we show how access to such communication resources could be granted to individual components (CAN bus connected ECUs) in the car by allowing transparent data transport using the standardized Internet Protocol (IP). Our experiments show that a complete IP Over CAN implementation, providing both UDP and TCP transport over IP, running on an Atmel AT90CAN128 is capable of transfer speeds up to 200 kbits while using less than 2 kbytes of dynamic RAM.

Place, publisher, year, edition, pages
Piscataway, NJ: IEEE Communications Society, 2008
Series
Industry Applications Society. I E E E - I A S Annual Meeting. Conference Record, ISSN 0197-2618
National Category
Embedded Systems
Research subject
Embedded System
Identifiers
urn:nbn:se:ltu:diva-29270 (URN)10.1109/ccnc08.2007.175 (DOI)000259262700169 ()2-s2.0-51949119382 (Scopus ID)2b02f2e0-7b3c-11dc-a72d-000ea68e967b (Local ID)978-1-424-41456-7 (ISBN)2b02f2e0-7b3c-11dc-a72d-000ea68e967b (Archive number)2b02f2e0-7b3c-11dc-a72d-000ea68e967b (OAI)
Conference
IEEE Consumer Communications and Networking Conference : 10/01/2008 - 12/01/2008
Projects
CASTT - Centre for Automotive Systems Technologies and Testing
Note
Validerad; 2008; 20071015 (pln)Available from: 2016-09-30 Created: 2016-09-30 Last updated: 2018-07-10Bibliographically approved
Lindgren, P., Nordlander, J., Aittamaa, S. & Eriksson, J. (2008). TinyTimber, reactive objects in C for real-time embedded systems (ed.). In: (Ed.), Donatella Sciuto (Ed.), Proceedings, Design, Automation and Test in Europe: DATE '08 ; Munich, Germany, 10 - 14 March 2008. Paper presented at Design, automation and test in Europe : 10/03/2008 - 14/03/2008 (pp. 1382-1385). New York: ACM Digital Library
Open this publication in new window or tab >>TinyTimber, reactive objects in C for real-time embedded systems
2008 (English)In: Proceedings, Design, Automation and Test in Europe: DATE '08 ; Munich, Germany, 10 - 14 March 2008 / [ed] Donatella Sciuto, New York: ACM Digital Library, 2008, p. 1382-1385Conference paper, Published paper (Refereed)
Abstract [en]

Embedded systems are often operating under hard real-time constraints. Such systems are naturally described as time-bound reactions to external events, a point of view made manifest in the high-level programming and systems modeling language Timber. In this paper we demonstrate how the Timber semantics for parallel reactive objects translates to embedded real-time programming in C. This is accomplished through the use of a minimalistic Timber Run-Time system, TinyTimber (TT). The TT kernel ensures state integrity, and performs scheduling of events based on given time-bounds in compliance with the Timber semantics. In this way, we avoid the volatile task of explicitly coding parallelism in terms of processes/threads/semaphores/monitors, and side-step the delicate task to encode time-bounds into priorities. In this paper, the TT kernel design is presented and performance metrics are presented for a number of representative embedded platforms, ranging from small 8-bit to more potent 32-bit micro controllers. The resulting system runs on bare metal, completely free of references to external code (even C-lib) which provides a solid basis for further analysis. In comparison to a traditional thread based real-time operating system for embedded applications (FreeRTOS), TT has tighter timing performance and considerably lower code complexity. In conclusion, TinyTimber is a viable alternative for implementing embedded real-time applications in C today.

Place, publisher, year, edition, pages
New York: ACM Digital Library, 2008
Series
ACM Conference Proceedings Series ; 1575
National Category
Embedded Systems Computer Sciences
Research subject
Embedded System; Dependable Communication and Computation Systems
Identifiers
urn:nbn:se:ltu:diva-32814 (URN)10.1109/DATE.2008.4484933 (DOI)2-s2.0-49749111469 (Scopus ID)76b3d470-7335-11dc-86ab-000ea68e967b (Local ID)978-3-9810801-3-1 (ISBN)76b3d470-7335-11dc-86ab-000ea68e967b (Archive number)76b3d470-7335-11dc-86ab-000ea68e967b (OAI)
Conference
Design, automation and test in Europe : 10/03/2008 - 14/03/2008
Projects
CASTT - Centre for Automotive Systems Technologies and Testing
Note
Godkänd; 2008; 20071005 (pln)Available from: 2016-09-30 Created: 2016-09-30 Last updated: 2018-07-10Bibliographically approved
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