Commit 26b9c12e by Jonas Künzli Committed by overleaf

### Update on Overleaf.

parent d99d3c5e
 ... ... @@ -254,9 +254,10 @@ $$U_p+U_s\leq 1$$ U_s &= \frac{C_s}{T_s} \end{align} When the $k$-th aperiodic request arrives at time $t=r_k$, it receives a deadline $$d_k=\max\{r_k,d_{k-1}\}+\frac{C_k}{U_s}$$ where $C_k$ is the When the $k$-th aperiodic request arrives at time $t=r_k$ , it receives a deadline (Tasks nach arrival times ordnen und deadlines berechnen) $$d_k=\max\{r_k,d_{k-1}\}+\frac{C_k}{U_s}$$ where $C_k$ is the execution time of the request and $U_s$ the server utilization factor (=bandwidth). $U_S$ can be chosen such that $U_s\leq 1-U_p$ (necessary and sufficient). sufficient).\newline The worst case finishing time of an aperiodic task is the calculated deadline.
 ... ... @@ -86,15 +86,28 @@ ES are expected to finish tasks reliably within time bounds.\\ Essential: Upper \end{compactitem} \includegraphics[width=0.6\linewidth]{symbols_cyclic_exec_scheduler} \textbf{Conditions}: \begin{compactitem} \item Process executes at most once within a frame:\\ $\forall$ Tasks $\tau_i$: $f \leq T_i$ \item $P$ is a multiple of $f$ \item Period $P$ is least common multiple of all periods $T_i$ \item Processes start and complete within a single frame: $\forall$ Tasks $\tau_i$: $f \geq C_i$ \item Between release time and deadline of a task, there is at least one frame boundary: $\forall$ Tasks $\tau_i$: $2f-\text{gcd}(T_i,f) \leq D_i$ \end{compactitem} ~\newline \textbf{Conditions}: \\ \begin{tabularx}{\columnwidth}{|X|X|} \hline Process executes at most once within a frame: & $f\leq T_i \quad \forall i$ \\ \hline $P$ is a multiple of $f$ & $\exists i: T_i \mod f = 0$ \\ \hline Processes start and complete within a single frame: & $f\geq C_i \quad \forall i$ \\ \hline Between release time and deadline of a task, there is at least one frame boundary: & $2f-\gcd (T_i,f)\leq D_i \quad \forall i$ \\ \hline \end{tabularx} Period $P$ is least common multiple of all periods $T_i$.\\ %\begin{compactitem} %\item Process executes at most once within a frame:\\ $\forall$ Tasks $\tau_i$: $f \leq T_i$ %\item $P$ is a multiple of $f$ %\item Period $P$ is least common multiple of all periods $T_i$ %\item Processes start and complete within a single frame: $\forall$ Tasks $\tau_i$: $f \geq C_i$ %\item Between release time and deadline of a task, there is at least one frame boundary: $\forall$ %Tasks $\tau_i$: $2f-\text{gcd}(T_i,f) \leq D_i$ %\end{compactitem} %~\newline \textbf{Check for correctness} of schedule: 4-32\\ \begin{itemize} ... ...
 ... ... @@ -80,6 +80,7 @@ A low priority task holds a Semaphore and prevents a high priority task from run \textbf{Problems:} \begin{itemize} \item Deadlocks: can be solved with Watchdog timers \includegraphics[width=0.5\linewidth]{images/deadlock.JPG} \end{itemize} ... ...
 ... ... @@ -34,7 +34,7 @@ Main sources: $f$ : & \quad Clock Frequency \\ $V_T$ : & \quad Threshold Voltage $V_T \ll V_{dd}$ \end{tabularx} ~\newline $P\propto V_{dd}^2$ and $f\propto V_{dd}^2$ so $P\propto V_{dd}^3$ \\ \ownsubsection{Basic Techniques (9-16)} \textbf{Power Supply Gating}: Cut off power supply to inactive units to reduce leakage ... ...
 ... ... @@ -44,9 +44,9 @@ $\to$ The main difference between general purpose processors and embedded system \end{compactitem} \ownsubsection{FPGA, Application Specific Circuits (ASICS) and SoC} $\to$ On every characteristic of an FPGA you loose a factor 10 vs ASIC. \textbf{ASIC}: If ultimate speed and energy efficiency are necessary and large numbers can be sold or there is a lot of money (military) $\to$ On every characteristic of an FPGA you loose a factor 10 vs ASIC.\\ \textbf{FPGA}:more flexible (reprogrammable)\\ \textbf{ASIC}: have a fixed application (not flexible),are harder to design,expensive, have a better fitting for specific application.\\If ultimate speed and energy efficiency are necessary and large numbers can be sold or there is a lot of money (military) \textbf{Trends}: \begin{compactitem} ... ...

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 ... ... @@ -5,7 +5,7 @@ \pagestyle{fancy} \lhead{Embedded Systems} \chead{FS19} \rhead{Very Cool Kids} \rhead{Very Cool Embedded System Kids} \begin{document} \begin{multicols*}{3} ... ...
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