+
+\section{Communication}
+All \gls{mTask} messages are encoded following the specification given in
+Appendix~\ref{app:communication-protocol}. Available messages are:
+\begin{lstlisting}[caption={Available messages}]
+:: MTaskMSGRecv
+ = MTTaskAck Int Int | MTTaskDelAck Int
+ | MTSDSAck Int | MTSDSDelAck Int
+ | MTPub Int BCValue | MTMessage String
+ | MTDevSpec MTaskDeviceSpec | MTEmpty
+
+:: MTaskMSGSend
+ = MTTask MTaskInterval String | MTTaskDel Int
+ | MTShutdown | MTSds Int BCValue
+ | MTUpd Int BCValue | MTSpec
+
+:: MTaskInterval = OneShot | OnInterval Int | OnInterrupt Int
+\end{lstlisting}
+
+\subsection{Add a device}
+A device can be added by filling in the \CI{MTaskDevice} record as much as
+possible and running the \CI{connectDevice} function. This function grabs the
+channels, starts the synchronization \gls{Task}, makes sure the errors are
+handled when needed and runs a processing function in parallel to react on the
+incoming messages. Moreover, it sends a specification request to the device in
+question to determine the details of the device and updates the record to
+contain the top-level \gls{Task}-id. All the device functionality heavily
+depends on the \CI{withDevices} function that applies a function a device in
+the \gls{SDS} when they are equal. Device equality is defined as equality on
+their channels. This allows you to give an old device record to the function
+and still update the latest instance. Listing~\ref{lst:connectDevice} shows the
+connection function.
+
+\begin{lstlisting}[label={lst:connectDevice},%
+ caption={Connect a device}]
+withDevices :: MTaskDevice (MTaskDevice -> MTaskDevice) -> Task [MTaskDevice]
+
+connectDevice :: (MTaskDevice (Shared Channels) -> Task ()) MTaskDevice -> Task Channels
+connectDevice procFun device = let ch = channels device
+ in appendTopLevelTask 'DM'.newMap True
+ (procFun device ch -||- catchAll (getSynFun d.deviceData ch) errHdl)
+ >>= \tid->withDevices device (\d->{d&deviceTask=Just tid,deviceError=Nothing})
+ >>| upd (\(r,s,ss)->(r,s++[MTSpec],ss)) ch
+ where
+ errHdl e = withDevices device (\d->{d & deviceTask=Nothing, deviceError=Just e}) @! ()
+\end{lstlisting}
+
+Figure~\ref{fig:handshake} shows the connection diagram. The client responds to
+the server with their device specification. This is detected by the processing
+function and the record is updated accordingly.
+
+\begin{figure}[H]
+ \begin{sequencediagram}
+ \newthread{s}{Server}
+ \newinst[4]{c}{Client}
+ \begin{call}{s}{MTSpec}{c}{MTDevSpec}
+ \end{call}
+ \end{sequencediagram}
+ \caption{Connect a device}\label{fig:handshake}
+\end{figure}
+
+\subsection{\glspl{Task}}
+\subsection{\glspl{SDS}}
+\todo{Connectie, hoe gaat dat in zijn werk}