Some rough copy'n'paste to pave path for an LPC connector
authored
Tue, 01 Dec 2009 13:48:47 +0100
changeset 448 8ef035de86de
parent 447 af3399aca7b7
child 449 9d5036e86c3d
Some rough copy'n'paste to pave path for an LPC connector
connectors/LPC/LPCObject.py
connectors/LPC/LPCProto.py
connectors/LPC/__init__.py
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/connectors/LPC/LPCObject.py	Tue Dec 01 13:48:47 2009 +0100
@@ -0,0 +1,177 @@
+#!/usr/bin/env python
+# -*- coding: utf-8 -*-
+
+#This file is part of Beremiz, a Integrated Development Environment for
+#programming IEC 61131-3 automates supporting plcopen standard and CanFestival. 
+#
+#Copyright (C) 2007: Edouard TISSERANT and Laurent BESSARD
+#
+#See COPYING file for copyrights details.
+#
+#This library is free software; you can redistribute it and/or
+#modify it under the terms of the GNU General Public
+#License as published by the Free Software Foundation; either
+#version 2.1 of the License, or (at your option) any later version.
+#
+#This library is distributed in the hope that it will be useful,
+#but WITHOUT ANY WARRANTY; without even the implied warranty of
+#MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+#General Public License for more details.
+#
+#You should have received a copy of the GNU General Public
+#License along with this library; if not, write to the Free Software
+#Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+
+from threading import Timer, Thread, Lock
+import ctypes, os, commands, types, sys
+import traceback
+
+class LPCObject():
+    _Idxs = []
+    def __init__(self,pluginsroot):
+        self.PLCStatus = "Stopped"
+        self.pluginsroot = pluginsroot
+        self.PLCprint = pluginsroot.logger.write
+    
+    def StartPLC(self, debug=False):
+        PLCprint("StartPLC")
+        if self.CurrentPLCFilename is not None:
+            self.PLCStatus = "Started"
+            self.PythonThread = Thread(target=self.PythonThreadProc, args=[debug])
+            self.PythonThread.start()
+            
+    def StopPLC(self):
+        PLCprint("StopPLC")
+        if self.PLCStatus == "Started":
+            self._stopPLC()
+            return True
+        return False
+
+    def ForceReload(self):
+        # respawn python interpreter
+        Timer(0.1,self._Reload).start()
+        return True
+
+    def GetPLCstatus(self):
+        return self.PLCStatus
+    
+    def NewPLC(self, md5sum, data, extrafiles):
+        PLCprint("NewPLC (%s)"%md5sum)
+        if self.PLCStatus in ["Stopped", "Empty", "Broken"]:
+            NewFileName = md5sum + lib_ext
+            extra_files_log = os.path.join(self.workingdir,"extra_files.txt")
+            try:
+                os.remove(os.path.join(self.workingdir,
+                                       self.CurrentPLCFilename))
+                for filename in file(extra_files_log, "r").readlines() + [extra_files_log]:
+                    try:
+                        os.remove(os.path.join(self.workingdir, filename.strip()))
+                    except:
+                        pass
+            except:
+                pass
+                        
+            try:
+                # Create new PLC file
+                open(os.path.join(self.workingdir,NewFileName),
+                     'wb').write(data)
+        
+                # Store new PLC filename based on md5 key
+                open(self._GetMD5FileName(), "w").write(md5sum)
+        
+                # Then write the files
+                log = file(extra_files_log, "w")
+                for fname,fdata in extrafiles:
+                    fpath = os.path.join(self.workingdir,fname)
+                    open(fpath, "wb").write(fdata)
+                    log.write(fname+'\n')
+
+                # Store new PLC filename
+                self.CurrentPLCFilename = NewFileName
+            except:
+                PLCprint(traceback.format_exc())
+                return False
+            if self.PLCStatus == "Empty":
+                self.PLCStatus = "Stopped"
+            return True
+        return False
+
+    def MatchMD5(self, MD5):
+        try:
+            last_md5 = open(self._GetMD5FileName(), "r").read()
+            return last_md5 == MD5
+        except:
+            return False
+    
+    def SetTraceVariablesList(self, idxs):
+        """
+        Call ctype imported function to append 
+        these indexes to registred variables in PLC debugger
+        """
+        self._suspendDebug()
+        # keep a copy of requested idx
+        self._Idxs = idxs[:]
+        self._ResetDebugVariables()
+        for idx in idxs:
+            self._RegisterDebugVariable(idx)
+        self._resumeDebug()
+
+    class IEC_STRING(ctypes.Structure):
+        """
+        Must be changed according to changes in iec_types.h
+        """
+        _fields_ = [("len", ctypes.c_uint8),
+                    ("body", ctypes.c_char * 127)] 
+    
+    TypeTranslator = {"BOOL" :       (ctypes.c_uint8, lambda x:x.value!=0),
+                      "STEP" :       (ctypes.c_uint8, lambda x:x.value),
+                      "TRANSITION" : (ctypes.c_uint8, lambda x:x.value),
+                      "ACTION" :     (ctypes.c_uint8, lambda x:x.value),
+                      "SINT" :       (ctypes.c_int8, lambda x:x.value),
+                      "USINT" :      (ctypes.c_uint8, lambda x:x.value),
+                      "BYTE" :       (ctypes.c_uint8, lambda x:x.value),
+                      "STRING" :     (IEC_STRING, lambda x:x.body[:x.len]),
+                      "INT" :        (ctypes.c_int16, lambda x:x.value),
+                      "UINT" :       (ctypes.c_uint16, lambda x:x.value),
+                      "WORD" :       (ctypes.c_uint16, lambda x:x.value),
+                      "WSTRING" :    (None, None),#TODO
+                      "DINT" :       (ctypes.c_int32, lambda x:x.value),
+                      "UDINT" :      (ctypes.c_uint32, lambda x:x.value),
+                      "DWORD" :      (ctypes.c_uint32, lambda x:x.value),
+                      "LINT" :       (ctypes.c_int64, lambda x:x.value),
+                      "ULINT" :      (ctypes.c_uint64, lambda x:x.value),
+                      "LWORD" :      (ctypes.c_uint64, lambda x:x.value),
+                      "REAL" :       (ctypes.c_float, lambda x:x.value),
+                      "LREAL" :      (ctypes.c_double, lambda x:x.value),
+                      } 
+                           
+    def GetTraceVariables(self):
+        """
+        Return a list of variables, corresponding to the list of required idx
+        """
+        if self.PLCStatus == "Started":
+            self.PLClibraryLock.acquire()
+            tick = self._WaitDebugData()
+            #PLCprint("Debug tick : %d"%tick)
+            if tick == 2**32 - 1:
+                tick = -1
+                res = None
+            else:
+                idx = ctypes.c_int()
+                typename = ctypes.c_char_p()
+                res = []
+        
+                for given_idx in self._Idxs:
+                    buffer=self._IterDebugData(ctypes.byref(idx), ctypes.byref(typename))
+                    c_type,unpack_func = self.TypeTranslator.get(typename.value, (None,None))
+                    if c_type is not None and given_idx == idx.value:
+                        res.append(unpack_func(ctypes.cast(buffer,
+                                                           ctypes.POINTER(c_type)).contents))
+                    else:
+                        PLCprint("Debug error idx : %d, expected_idx %d, type : %s"%(idx.value, given_idx,typename.value))
+                        res.append(None)
+            self._FreeDebugData()
+            self.PLClibraryLock.release()
+            return tick, res
+        return -1, None
+
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/connectors/LPC/LPCProto.py	Tue Dec 01 13:48:47 2009 +0100
@@ -0,0 +1,88 @@
+import serial
+from threading import Lock
+
+LPC_CMDS=dict(IDLE = 0x00,
+              START = 0x01,
+              STOP = 0x02,
+              SET_TRACE_VARIABLE = 0x04,
+              GET_TRACE_VARIABLES = 0x05,
+              SET_FORCED_VARIABLE = 0x06,
+              GET_PLCID = 0x07)
+
+WAIT_DATA = 0x04
+
+LPC_STATUS=dict(STARTED = 0x01,
+                STOPPED = 0x02,
+                DEBUG = 0x03)
+
+class LPCError(exceptions.Exception):
+        """Exception class"""
+        def __init__(self, msg):
+                self.msg = msg
+                return
+
+        def __str__(self):
+                return "LPC communication error ! " + str(self.msg)
+
+class LPCProto:
+    def __init__(self, port, rate, timeout):
+        # open serial port
+        self.serialPort = serial.Serial( port, rate, timeout = timeout )
+        self.serialPort.flush()
+        # handshake
+        self.HandleTransaction(LPCTransaction("IDLE"))
+        # serialize access lock
+        self.TransactionLock = Lock()
+    
+    def HandleTransaction(self, transaction):
+        self.TransactionLock.acquire()
+        try:
+            transaction.SetPseudoFile(self.serialPort)
+            # send command, wait ack (timeout)
+            transaction.SendCommand()
+            current_plc_status = transaction.GetCommandAck()
+            if current_plc_status is not None:
+                res = transaction.ExchangeData()
+            else:
+                raise LPCError("LPC transaction error - controller did not answer as expected")
+        finally:
+            self.TransactionLock.release()
+        return current_plc_status, res
+    
+class LPCTransaction:
+    def __init__(self, command, optdata):
+        self.Command =  LPC_CMDS[command]
+        self.OptData = optdata[:]
+        self.serialPort = None
+        
+    def SetPseudoFile(pseudofile):
+        self.pseudofile = pseudofile
+        
+    def SendCommand(self):
+        # send command thread
+        self.pseudofile.write(chr(self.Command))
+        
+    def GetCommandAck(self):
+        comm_status, current_plc_status = map(ord, self.pseudofile.read(2))
+        # LPC returns command itself as an ack for command
+        if(comm_status == self.Command):
+            return current_plc_status
+        return None 
+        
+    def ExchangeData(self):
+        if self.Command & WAIT_DATA :
+            length = len(self.OptData)
+            # transform length into a byte string
+            # we presuppose endianess of LPC same as PC
+            lengthstr = ctypes.string_at(ctypes.pointer(ctypes.c_int(length)),4) 
+            self.pseudofile.write(lengthstr + self.OptData)
+            
+            lengthstr = self.pseudofile.read(4)
+            # transform a byte string into length 
+            length = ctypes.cast(ctypes.c_char_p(lengthstr), ctypes.POINTER(ctypes.c_int)).contents.value
+            return self.pseudofile.read(length)
+        return None
+        
+if __name__ == "__main__":
+    TestConnection = LPCProto()
+    
\ No newline at end of file
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/connectors/LPC/__init__.py	Tue Dec 01 13:48:47 2009 +0100
@@ -0,0 +1,87 @@
+#!/usr/bin/env python
+# -*- coding: utf-8 -*-
+#
+#Copyright (C) 2007: Edouard TISSERANT and Laurent BESSARD
+#
+#See COPYING file for copyrights details.
+#
+#This library is free software; you can redistribute it and/or
+#modify it under the terms of the GNU General Public
+#License as published by the Free Software Foundation; either
+#version 2.1 of the License, or (at your option) any later version.
+#
+#This library is distributed in the hope that it will be useful,
+#but WITHOUT ANY WARRANTY; without even the implied warranty of
+#MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+#General Public License for more details.
+#
+#You should have received a copy of the GNU General Public
+#License along with this library; if not, write to the Free Software
+#Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+import traceback
+
+
+def LPC_connector_factory(uri, pluginsroot):
+    """
+    This returns the connector to LPC style PLCobject
+    """
+    pluginsroot.logger.write(_("Connecting to URI : %s\n")%uri)
+
+    servicetype, location = uri.split("://")
+    
+    # Try to get the proxy object
+    try :
+        # TODO: Open Serial Port
+        RemotePLCObjectProxy = LPCObject(pluginsroot) # LPC_PLCObject_Proxy
+    except Exception, msg:
+        pluginsroot.logger.write_error(_("Couldn't connect !\n"))
+        pluginsroot.logger.write_error(traceback.format_exc())
+        return None
+
+    def LPCCatcher(func, default=None):
+        """
+        A function that catch a pyserial exceptions, write error to logger
+        and return defaul value when it happen
+        """
+        def catcher_func(*args,**kwargs):
+            try:
+                return func(*args,**kwargs)
+            except Exception,e:
+                #pluginsroot.logger.write_error(traceback.format_exc())
+                pluginsroot.logger.write_error(str(e)+"\n")
+                pluginsroot._connector = None
+                return default
+        return catcher_func
+
+    # Check connection is effective. 
+    # lambda is for getattr of GetPLCstatus to happen inside catcher
+    if LPCCatcher(lambda:RemotePLCObjectProxy.GetPLCstatus())() == None:
+        pluginsroot.logger.write_error(_("Cannot get PLC status - connection failed.\n"))
+        return None
+
+
+    class LPCProxy:
+        """
+        A Serial proxy class to handle Beremiz Pyro interface specific behavior.
+        And to put LPC exception catcher in between caller and pyro proxy
+        """
+        def _LPCGetTraceVariables(self):
+            return self.RemotePLCObjectProxy.GetTraceVariables()
+        GetTraceVariables = LPCCatcher(_LPCGetTraceVariables,("Broken",None,None))
+
+        def _LPCGetPLCstatus(self):
+            return RemotePLCObjectProxy.GetPLCstatus()
+        GetPLCstatus = LPCCatcher(_LPCGetPLCstatus, "Broken")
+        
+        def __getattr__(self, attrName):
+            member = self.__dict__.get(attrName, None)
+            if member is None:
+                def my_local_func(*args,**kwargs):
+                    return RemotePLCObjectProxy.__getattr__(attrName)(*args,**kwargs)
+                member = LPCCatcher(my_local_func, None)
+                self.__dict__[attrName] = member
+            return member
+
+    return LPCProxy()
+    
+