OK nearly got the software PID example

finished, one last push....

mybib.bib

@@ -1,3 +1,39 @@
+@INPROCEEDINGS{5488118, 
+author={Pace, C. and Libertino, S. and Crupi, I. and Marino, A. and Lombardo, S. and Sala, E.D. and Capuano, G. and Lisiansky, M. and Roizin, Y.}, 
+booktitle={Instrumentation and Measurement Technology Conference (I2MTC), 2010 IEEE}, title={Compact instrumentation for radiation tolerance test of flash memories in space environment}, 
+year={2010}, 
+month={may}, 
+volume={}, 
+number={}, 
+pages={652 -655}, 
+keywords={FPGA-based design;compact instrumentation;failure data screening;flash memories;latch-up protection;nonvolatile memory arrays;radiation tolerance test;space environment;flash memories;radiation hardening (electronics);random-access storage;tolerance analysis;}, 
+doi={10.1109/IMTC.2010.5488118}, 
+ISSN={1091-5281},}
+
+@INPROCEEDINGS{5963919, 
+author={Ghahroodi, M.M. and Zwolinski, M. and Ozer, E.}, 
+booktitle={Adaptive Hardware and Systems (AHS), 2011 NASA/ESA Conference on}, title={Radiation hardening by design: A novel gate level approach}, 
+year={2011}, 
+month={june}, 
+volume={}, 
+number={}, 
+pages={74 -79}, 
+keywords={SEU tolerant flip-flop design;SEU-tolerant clock-gating scheme;TMR;area-power overheads;electronic circuits;electronic systems;gate level approach;radiation-hardening techniques;sea-level applications;single-event-upset tolerant flip-flop design;size 65 nm;triple modular redundancy;flip-flops;integrated circuit reliability;logic design;radiation hardening (electronics);}, 
+doi={10.1109/AHS.2011.5963919}, 
+ISSN={},}
+
+@INPROCEEDINGS{swseatbelt, 
+author={Emery D Berger}, 
+booktitle={Communications of the ACM}, title={Software needs seatbelts and Airbags}, 
+year={2012}, 
+month={september}, 
+volume={}, 
+number={}, 
+pages={48 - 56}, 
+keywords={software reliability}, 
+ISSN={Doi:10.1145/2330667.2330683},}
+
+
 @Book{dcods,
 	author = {Franklin,Powell,Workman},
 	title = {Digital Control of Dynamic Systems},

submission_thesis/CH5_Examples/software.tex

@@ -33,7 +33,7 @@ of its inputs as failure modes---we can
 determine its symptoms of failure (i.e. how calling functions will see its failure mode behaviour).
 
 %
-We   apply the FMMD process to software functions by viewing them in terms of their failure mode behaviour. 
+We apply the FMMD process to software functions by viewing them in terms of their failure mode behaviour. 
 %
 As software already fits into a hierarchy we have one less analysis decision to make, compared
 to analysing electronics. 
@@ -601,9 +601,9 @@ software component $read\_4\_20\_input$, i.e. $G_3 = \{read\_4\_20\_input, RADC\
                                &  i.e. < 0.88V  &                   \\                          
                                \hline
     
+   5:  post condition fails                 &  software fails              &          $VAL\_ERR$                  \\ \hline
+
 \hline
-
-
 \hline
 
 \end{tabular}
@@ -755,6 +755,7 @@ For the output, we can use a Pulse Width Modulator (PWM) (this is a common modul
 allowing a variable power output~\cite{pwm}). PWM's ADC's and MUX's are commonly built into cheap micro-controllers~\cite{pic18f2523}.
 We can now build more detail into the Yourdon diagram, with the afferent data flow coming through the MUX and ADC on the micro-controller, and the efferent 
 channelled through a PWM module, %again built into the micro-controller, 
+%
 see figure~\ref{fig:context_diagram2_PID}.
 \begin{figure}[h]+
  \centering
@@ -837,8 +838,9 @@ Identified electronic components:
  \item HEATER --- Heating element, essentially a resistor.
  \item Pt100 --- Pt100 Temperature sensor, as analysed in section~\ref{sec:Pt100}.
  \item PWM --- Internal micro controller pulse width modulation module
+ \item General Purpose I/O (GPIO) --- 
+ \item LEDs --- Indication LEDs via GPIO
  \item micro-controller --- the medium for running the software
- \item setLEDs --- Set status indication LEDs via GPIO
 \end{itemize}
 
 
@@ -1297,12 +1299,74 @@ We apply FMMD analysis to this {\fg} in table~\ref{tbl:ledoutput}.
 
 
 
+\subsubsection{Final Analysis Stage: PID Temperature Controller}
+
+The possibility of each software function failing its post condition without a direct
+underlying cause from one of its components has been included in each analysis stage 
+involving software. This is because software introduces the possibility of
+anything going wrong! The common causes for software failing are:
+\begin{itemize}
+ \item Value/RAM corruption typically from interrupt contention problems or accidental over writing~\cite{swseatbelt}, 
+ but can be from external sources such as radiation changing bits/values at runtime~\cite{5963919, 5488118};
+ \item Address bus errors leading to program errors (program sequence);
+ \item ROM memory failures;
+ \item Unintended behaviour of software.
+\end{itemize}
+Because the software is running on a medium, that of the processor or micro-controller
+our design at the final or highest level (see table~\ref{tbl:pid}), must include all possible failure modes of this medium i.e.
+$$fm (micro-controller) =\{ PROM\_FAULT, RAM\_FAULT, CPU\_FAULT, ALU\_FAULT, CLOCK\_STOPPED \}.$$
+We perform the final FMMD stage by forming a functional group with the {\dcs}
+determined previously:
+%
+\begin{itemize}
+ \item PID
+ \item HeaterOutput
+ \item LEDoutput
+ \item and the function `monitor'. 
+\end{itemize}
+
+The post condition for the monitor function is that it implements the PID control task correctly.
 
 
+{
+\tiny
+\begin{table}[h+]
+\caption{ PID standalone controller: Failure Mode Effects Analysis} % title of Table
+\label{tbl:pid}
 
-
+\begin{tabular}{|| l   | c |   l ||} \hline
-
+% \textbf{Failure}   &  \textbf{failure}     & \textbf{Symptom}          \\ 
-
+% \textbf{Scenario}  &  \textbf{effect}      &     \textbf{RADC }                     \\ \hline 
+ \hline 
+ \textbf{Failure} &  \textbf{Failure }         & \textbf{Derived Component}          \\ 
+ \textbf{cause}   &   \textbf{Effect}                & \textbf{Failure Mode}          \\
+  
+ 
+               \hline
+     FC1: $ Temp LED fails $      &   LED will not light       & FailureIndicated         \\  
+                                  &                            &                 \\  \hline    
+                                       
+                                         
+       FC2: $ Processor LED fails $           &   LED will not light          &  FailureIndicated               \\  
+                                              &                               &                 \\  \hline    
+                                        
+          FC3: $ PWM LED fails $           &  LED will not light         &  FailureIndicated               \\  
+                                          &                              &                 \\  \hline
+                                          
+           FC4:  GPIO stuck HIGH & LED permanently OFF &   FailureIndicated    \\ \hline
+           
+ 
+           FC5: GPIO stuck Low  & LED permanently ON &   FailureIndicated    \\ \hline
+           
+           
+            FC6:  Software SetLEDs                 &  Incorrect Indication        &  IndicationError               \\  
+                  fails to set outputs correctly   &   Post condition failure     &                 \\  \hline                                             
+  
+                                        
+                                        
+\end{tabular}
+\end{table}
+}