add notion on existential types, update interface

diff --git a/arch.example.tex b/arch.example.tex
index db9a2a7..a5f3684 100644 (file)
--- a/arch.example.tex
+++ b/arch.example.tex
@@ -4,7 +4,7 @@ pattern. First the devices are created --- with or without the interaction of
 the user --- and they are then connected. When all devices are registered, the
 \gls{mTask}-\glspl{Task} can be sent and \gls{iTasks}-\glspl{Task} can be
 started to monitor the output. When everything is finished, the devices are
-removed and the system is powered off.
+removed and the system is shut down.
 
 \begin{lstlisting}[language=Clean,label={lst:framework},
        caption={\gls{mTask} framework for building applications}]
@@ -14,8 +14,7 @@ w =         makeDevice "dev1" (...) >>= connectDevice
        >>= \dev2->...
        ...
        >>* [OnAction (Action "Shutdown") $ always
-               $   deleteDevice dev1
-               >>| deleteDevice dev2
+               $   deleteDevice dev1 >>| deleteDevice dev2
                >>| ...
                >>| shutDown 0
        ]
@@ -23,8 +22,36 @@ w =         makeDevice "dev1" (...) >>= connectDevice
 
 \subsection{Thermostat}
 The thermostat is a classic example program for showing interactions between
-peripherals. The following program shows a system containing two devices. One
-device is connected via \gls{TCP} and contains a temperature sensor. The second
+peripherals. The following program shows a system containing two devices. The
+first device --- the sensor -- contains a temperature sensor that measures the
+room temperature. The second device --- the actor --- contains a heater,
+connected to the digital pin \CI{D5}. Moreover, this device contains a led to
+indicate whether the heater is on. The following code shows an implementation
+for this. The code fully uses the framework. Note that a little bit of type
+twiddling is required to fully us the result from the \gls{SDS}. This approach
+is still type safe due to the type safety of \CI{Dynamic}s.
+
+\begin{lstlisting}[caption={Thermostat example}]
+thermos :: Task ()
+thermos =           makeDevice "nodeM" nodeMCU >>= connectDevice
+       >>= \nod->      makeDevice "stm32" stm32   >>= connectDevice
+       >>= \stm->      sendTaskToDevice "sensing" sensing (nod, OnInterval 1000)
+       >>= \(st, [t])->sendTaskToDevice "acting" acting (stm, OnInterval 1000)
+                       (\(BCValue s)->set (BCValue $ dynInt (dynamic s) > 0) (shareShare nod a))
+       >>| treturn ()
+where
+       dynInt :: Dynamic -> Int
+       dynInt (a :: Int) = a
+
+       sensing = sds \x=0 In {main=
+                       x =. analogRead A0 :. pub x
+               }
+       acting = sds \cool=False In {main=
+                       IF cool (ledOn LED1) (ledOff LED1) :.
+                       digitalWrite D5 cool
+               }
+       nodeMCU = TCP
+\end{lstlisting}
 
 \subsection[Lifting mTasks to iTasks-Tasks]%
        {Lifting \gls{mTask}-\glspl{Task} to \gls{iTasks}-\glspl{Task}}
@@ -34,7 +61,7 @@ an \gls{iTasks}-\gls{Task}. The function is called with a name, \gls{mTask},
 device and interval specification and it will return a \gls{Task} that finishes
 if and only if the \gls{mTask} has returned.
 
-\begin{lstlisting}[caption={Starting up the devices}]
+\begin{lstlisting}[caption={Lifting \gls{mTask}-\glspl{Task} to \gls{iTasks}}]
 liftmTask :: String (Main (ByteCode () Stmt)) (MTaskDevice, MTaskInterval) -> Task [MTaskShare]
 liftmTask wta mTask c=:(dev, _)= sendTaskToDevice wta mTask c
        >>= \(t, shs)->wait "Waiting for mTask to return" (taskRemoved t) (deviceShare dev)
@@ -59,3 +86,11 @@ where
                        ( pub x :. retrn                  )
                        ( x =. x *. y :.  y =. y -. lit 1 )}
 \end{lstlisting}
+
+\subsection{Heartbeat \& Oxygen Saturation Sensor}
+As an example, the addition of a new sensor will be demonstrated. The heartbeat
+and oxygen saturation sensor is a \textsc{PCB} the size of a fingernail with a
+red \gls{LED} and a light sensor on it. Moreover, it contains an \textsc{I2C}
+chip to communicate. The company producing the chip provides the programmer
+with example code for \gls{Arduino} and \textsc{mbed}. So suppose %TODO
+Adding peripheral is supposedly simple.

diff --git a/listings/interface.h b/listings/interface.h
index 7faaab2..31fa4d3 100644 (file)
--- a/listings/interface.h
+++ b/listings/interface.h
@@ -1,24 +1,29 @@
 #ifndef INTERFACE_H
 #define INTERFACE_H
 
+#ifdef __cplusplus
+extern "C" {
+#endif
+
 #include <stdbool.h>
 #include <stdint.h>
 #include <stdarg.h>
 
 #ifdef LINUX
-#define APINS 7
-#define DPINS 14
+#define APINS 128
+#define DPINS 128
 #define STACKSIZE 1024
 #define MEMSIZE 1024
 #define HAVELED 1
+#define HAVEHB 1
 #elif defined STM
 ...
 #endif
 
 /* Communication */
-bool input_available(void);
+bool    input_available(void);
 uint8_t read_byte(void);
-void write_byte(uint8_t b);
+void    write_byte(uint8_t b);
 
 /* Analog and digital pins */
 #if DPINS > 0
@@ -26,7 +31,7 @@ void write_dpin(uint8_t i, bool b);
 bool read_dpin(uint8_t i);
 #endif
 #if APINS > 0
-void write_apin(uint8_t i, uint8_t a);
+void    write_apin(uint8_t i, uint8_t a);
 uint8_t read_apin(uint8_t i);
 #endif
 
@@ -36,14 +41,25 @@ void led_on(uint8_t i);
 void led_off(uint8_t i);
 #endif
 
+#if HAVEHB == 1
+uint16_t get_hb();
+bool     valid_hb();
+uint16_t get_spo2();
+bool     valid_spo2();
+#endif
+
 /* Delay and communication */
 unsigned long getmillis(void);
 void msdelay(unsigned long ms);
 
 /* Auxilliary */
 void real_setup(void);
-void debug(char *fmt, ...);
+void real_debug(char *fmt, ...);
 void pdie(char *s);
 void die(char *fmt, ...);
+void reset(void);
 
+#ifdef __cplusplus
+}
+#endif
 #endif

diff --git a/mtaskext.bytecode.tex b/mtaskext.bytecode.tex
index 833d964..33f5f70 100644 (file)
--- a/mtaskext.bytecode.tex
+++ b/mtaskext.bytecode.tex
@@ -24,7 +24,10 @@ the content. Most notably, the type must be bytecode encodable. A \CI{BCValue}
 must be encodable and decodable without losing type or value information. At
 the moment a simple encoding scheme is used that uses single byte prefixes to
 detect the type of the value. The devices know these prefixes and can apply the
-same detection if necessary.
+same detection if necessary. Note that \CI{BCValue} uses existentially
+quantified type variables and therefore it is not possible to derive class
+instances such as \CI{iTasks}. Tailor-made instances for these functions have
+been made.
 
 \begin{lstlisting}[label={lst:bcview},caption={Bytecode view}]
 :: ByteCode a p = BC (RWS () [BC] BCState ())