- Added back calculation from motor positions to Q/E variables into

TAS code.
- Fixed communication problems in SerPortServer, mainly with terminator
  detection.
- Added SPS switched motors for TOPSI
- Debugged Power-PC histogram memory software for TRICS

switchedmotor.w

@@ -0,0 +1,97 @@
+\subsection{Switched Motors}
+At TOPSI there is a set of motors which share a single EL734 motor slot. Which
+ motor is adressed is switched via a SPS. The idea was to save money but really
+ this is a pain in the ass. Especially as the motors do not have own encoders.
+ This module implements sofwtare support for this setup. Virtual motors are
+ defined for the slave motors. The algorithm implemented works as follows:
+
+There is always an active motor which is currently adressed. When
+{\bf reading } the motor either a stored value is returned (when the
+motor is not adressed) or the real value is read from the motor. When
+driving a motor the following things happen:
+\begin{itemize}
+\item If the motor is active the motor is directly driven.
+\item If the motor is not active:
+\begin{itemize}
+\item The correct motor is switched to in the SPS.
+\item A reference run is made.
+\item The motor is finally driven.
+\end{itemize}
+\end{itemize}
+
+
+In order to do all this we need yet another data structure:
+
+@d swdata @{
+	typedef struct __SWMOT {
+	                       pObjectDescriptor pDes;
+	                       pIDrivable pDriv;
+	                       pMotor pMaster;
+	                       int *selectedMotor;
+	                       int myNumber;
+	                       float positions[3];
+	                       char slaves[3][80];
+	                       char *switchFunc;
+                               int errCode;
+                               } SWmot, *pSWmot;
+@}
+
+The fields are:
+\begin{description}
+\item[pDes] The standard SICS object descriptor.
+\item[pDriv] The drivable interface.
+\item[pMaster] The EL734 motor used as the master motor for driving
+ the slaves.
+\item[myNumber] The number of the motor implemented by this object.
+\item[selectedMotor] The number of the selected motor. This must be a
+pointer in order to be shared among multiple copies of this.
+\item[slaves] The names of the slave motors.  
+\item[switchFunc] is the name of a interpreter function which does 
+ the switching to another motor. Usually this will be implemented in
+Tcl. This gives some level of portability to other setups. The syntax
+shall be : status = switchFun motNumber. status will either hold OK on
+ return or the error encountered. 
+\item[errCode] is an internal error code.
+\end{description}
+
+Of course there will be three copies of this structure for the three
+slave motors. 
+
+Most feautures of this module will be implemented in the functions of
+the drivable interface or internal functions. The only additional
+functions needed provide the interface for the interpreter:
+
+@d swint @{
+  int MakeSWMotor(SConnection *pCon, SicsInterp *pSics, void *pData,
+                   int argc, char *argv[]);
+
+  int SWMotorAction(SConnection *pCon, SicsInterp *pSics, void *pData,
+                   int argc, char *argv[]);
+@}
+
+@o swmotor.h @{
+/*----------------------------------------------------------------------
+  TOPSI switched motors. Three motors share a EL734 motor. Between is
+  switched through a SPS. 
+
+  Mark Koennecke, May 2001
+-----------------------------------------------------------------------*/
+#ifndef SWMOTOR
+#define SWMOTOR
+#include "obdes.h"
+#include "interface.h"
+#include "motor.h"
+@<swint@>
+#endif 
+@}
+
+@o swmotor.i @{
+/* ----------------------------------------------------------------------
+ Internal data structure for the switched motor module. For
+ documentation see swmotor.tex.
+
+ Mark Koennecke, May 2001
+----------------------------------------------------------------------*/
+@<swdata@>
+ 
+@}