%! TEX root = ../thesis.tex


\chapter{Introduction}

\section{What is the BrainScale System?}

The BrainScaleS Wafer System, developed and used in the electronic visions Group at Heidelberg University is a neuromorhic hardware implementation.

For this Thesis important core components, inside the System, are the mixed-signal ASICs, named HICANNs (on Wafer in fig. \ref{wss}), and FPGAs for controlling these HICANNs \cite{hbpguidebook-brainscales}

\begin{figure}[h]
    \centering
    \includegraphics[width=.9\textwidth]{pics/waferscale_system.png}
    \caption{The BrainScaleS wafer-scale hardware system}
    \label{wss}
\end{figure}

\section{What's the PowerIt Subsystem?}

The hardware used in this thesis is a PowerIt board (fig. \ref{}), developed in the electronic visions group. It functions as power supply inside of the Waferscale System (fig. \ref{wss}). 

\begin{figure}[h]
    \centering
    \includegraphics[width=.9\textwidth]{pics/poweritv2_teststand_2}
    \caption{PowerIt Board top view, in test}
    \label{}
\end{figure}

In which it is providing the Wafer with 1.8V and the FPGAs with 9.6V. Its maximum rated Pwerdraw is 2kW. 

%TODO: fix cite \cite{poweritpgrade}

<containing intro to system and board>

%TODO: mv to theory <contains circuits to all measureing adcs, and description of the measureing process>

\newpage
\section{Goals}
\begin{itemize}
    \item Upgrade the PowerIt Firmware to contain the ability for calibration of all on board measurements, voltage and current.

        This requires the Firmware to handle calibration changes on the fly, also without assuming the degree of polynomials used (only that they are all of the same degree) 
    \item Provide a communication interface for changing those parameters on runtime.

        Assuming v2 of the communication Protocol (PItCOMM) we require access to all coefficients as writable objects, defining the degree of polynomial needs to be set here, resulting in setting the polynomial degrees at compile time.
    \item Provide access to more parameters used within the PowerIt while unifying the protocol used.

        Collect all writable, readable and static parameters in a single interface using PItCOMM v2, creating a mapping for reference to those values.
    \item Calibrate the onboard measurement circuits, using a database containing uniquely mappable values.

        Characterizing the circuits, providing a default for fallback and a Database file, readable by the BrainScaleS Monitoring System and the Person calibrating each Board.
    \item Provide a manual for calibrating additional PowerIt Boards.

        This should contain all commands to be run on each device which is part of the calibration process, as well as instructions for writing new values to the database.
    \item Using the calibrated measurements provide a regulation mechanism for stable 1.8V output at its endpoint.

        The connection between PowerIt and HICANNs can be seen as a non trivial Resistor, which requires the 1.8V output to regulate based on experimental data.
\end{itemize}
