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In recent years, more and more vendors adopt Linux to be the embedded operating system for their electronic products because of its combination of reliability, performance, good toolchains, portability, and configurability. However, Linux kernel is complex, and different electronic products may use different platforms. For this reason, it often requires that Linux be ported to different platforms. Vedio and sound have been supported by Linux for a long time. The Open Sound System (OSS) plays an important role in Linux¡¦s sound system. OSS is a device driver for sound cards and other sound devices under various UNIX and UNIX-compatible operating systems. The biggest problem with OSS is that the free implementation that exists in the Kernel is quite limited. For a better support of modern sound cards, a new sound driver project was started by Jaroslav Kysela and others. Jaroslav Kysela started with a sound driver he needed to supporta sound card, and this grew into the ALSA project which he co-ordinates. More and More people become involved in the development of ALSA. This thesis can be divided into two parts. In the first part, we give a detailed description of how we port ALSA to an embedded system, which include both ALSA driver and ALSA library. In the second part, we turn our attention to applications that rely on ALSA, which include a PCM recorder, a PCM player, and a MP3 player.

The work described in this thesis summarizes the author's contributions to the design, development, and testing of embedded systems for SFL spacecraft. The unique environment of space and the constraints it imposes on embedded systems is described, and the testing methodologies employed to qualify spacecraft hardware for this environment are presented. The implementation of an automated functional test framework for SFL's Generic Nanosatellite Bus satellites and the role it plays in the spacecraft development cycle is also discussed. Application software and device drivers in support of the BRITE mission were designed and developed. Finally, a controller was implemented for thermal control of the BRITE optical instrument. These contributions play an important role in the continual efforts to expand access to space and to prove the feasibility of the microspace approach in doing so.

The work described in this thesis summarizes the author's contributions to the design, development, and testing of embedded systems for SFL spacecraft. The unique environment of space and the constraints it imposes on embedded systems is described, and the testing methodologies employed to qualify spacecraft hardware for this environment are presented. The implementation of an automated functional test framework for SFL's Generic Nanosatellite Bus satellites and the role it plays in the spacecraft development cycle is also discussed. Application software and device drivers in support of the BRITE mission were designed and developed. Finally, a controller was implemented for thermal control of the BRITE optical instrument. These contributions play an important role in the continual efforts to expand access to space and to prove the feasibility of the microspace approach in doing so.

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This project aimed to create a simple open-source embedded graphical user interface library that could be used on more or less any microcontroller platform. The programming language was intended to be C++ for the GUI but as the project evolved C was chosen above C++. This was a decision based primarily on the fact that STM's development environment, STMCubeIDE, is less compatible with C++. The IDE offers great hardware support which in the end was more important than the advantages given by C++. The hardware used in this project was an STM32F469 microcontroller. It has an ARM CortexM4 processor core and 2 Mbyte of flash memory and 384 Kbytes of RAM. Wrapper functions for the Board Support Package, BSP, were written as a part of the library to allow easy access tothe BSP needed for the hardware configuration. The first part of the project goal was achieved, a simple GUI library was created. The resulting GUI library supports user interaction through buttons, it can display the current time andvisualizes given data in graphs. The graph function can display the data live, as a scatter plot, a bar plot and a line plot. The library also supports an alarm function that allows the user to decide what will happen after the alarm time is up. However, even though the GUI library was written to be device-independent, the product has not been tested on other platforms. For further development, this GUI library could be tested on another microcontroller. This would provide answers to how much software changes are needed to make the product as hardwareindependent as possible. To make the library lighter and faster, there is a possibility of optimizing the GUI core.

No description available.

This paper discusses the design of an autonomous remote-controlled racecar to play a one-on-one match of capture the flag. A competition was held, and the results are presented and conclusions are made.

With the advent of energy harvesters, supporting fast and efficient computation on energy harvesting devices has become a key challenge in the field of energy harvesting on ubiquitous devices. Computation on energy harvesting devices is equivalent to spreading the execution time of a lasting application over short, frequent cycles of power. However, we must ensure that results obtained from intermittently executing an application do produce results that are congruent to those produced by executing the application on a device with a continuous source of power. The current state-of-the-art systems that enable intermittent computation on energy harvesters make use of novel compiler analysis techniques as well as on-board hardware on devices to measure the energy remaining for useful computation. However, currently available programming models, which mostly target devices with FRAM as the NVM, would cause failure on devices that employ the Flash as primary NVM, thereby resulting in a non-universal solution that is restricted by the choice of NVM. This is primarily the result of the Flash's limited read/write endurance. This research aims to contribute to the world of energy harvesting devices by providing solutions that would enable intermittent computation regardless of the choice of NVM on a device by utilizing only the SRAM to save state and perform computation. Utilizing the SRAM further reduces run-time overhead as SRAM reads/writes are less costlier than NVM reads/writes. Our proposed solutions rely on programmer-guidance and compiler analysis to correct and efficient intermittent computation. We then extend our system to provide a complete compiler-based solution without programmer intervention. Our system is able to run applications that would otherwise render any device with Flash as NVM useless in a matter of hours. / Master of Science / As batteries continue to take up space and make small-scale sensors hefty, battery-less devices have grown increasingly popular for non-resource intensive computations. From tracking air pressure in vehicle tires to monitoring room temperature, battery-less devices have countless applications in various walks of life. These devices function by periodically harvesting energy from the environment and its surroundings to power short bursts of computation. When device energy levels reach a lower-bound threshold these devices must power off to scavenge useful energy from the environment to further perform short bursts of computation. Usually, energy harvesting devices draw power from solar, thermal or RF energy. This vastly depends on the build of the device, also known as a microprocessor (a processing unit built to perform small-scale computations). Due to these devices constantly powering on and off, performing continuous computation on such devices is rather more difficult when compared to systems with a continuous source of power. Since applications can require more time to complete than one power cycle of such devices, by default, applications running on these devices will restart execution from the beginning at the start of every power cycle. Therefore, it is necessary for such devices to have mechanisms to remember where the were before the device lost power. The past decade has seen many solutions proposed to aid an application in restarting execution rather than recomputing everything from the beginning. Solutions utilize different categories of devices with different storage technologies as well different software and hardware utilities available to programmers in this domain. In this research, we propose two different low-overhead, long-life computation models to support intermittent computation on a subset of energy harvesting devices which use Flash-based memory to store persistent data. Our approaches are heavily dependent on programmer guidance and different program analysis techniques to sustain computation across power cycles.

This thesis explores the security of intermittent devices, embedded systems designed to retain their state across periods of power loss, for cases both when the device has an excess of available energy and when power loss is unavoidable. Existing work with intermittent systems has focused on the problems inherent to the intermittent paradigm and ignored the security implications of persistent state across periods of power loss. The security of these devices is closely linked to their unique operational characteristics and are addressed here in two studies. First, the presence of an energy harvester creates an opportunity to use excess energy, available when additional energy is harvested after the local energy reservoir is filled, to precompute security related operations. Precomputation powered by this excess energy can reduce the cost of expensive tasks during periods of energy scarcity, potentially enabling the use of expensive security operations on traditionally unsecured devices. Second, when energy is limited and intermittent operation is required, the secure storage of checkpoints is a necessity to protect against adversary manipulation of the system state. To examine the secure storage of checkpoints a protocol is implemented to ensure the integrity and authenticity of a device's checkpoints, and evaluated for its energy overhead and performance. The cost of properly ensuring the integrity and authenticity of these checkpoints is examined to identify the overhead necessary to execute intermittent operations in a secure manner. Taken together, these studies lay the groundwork for a comprehensive view of the current state of intermittent device security. / Master of Science