1

import ctypes

     2

from LPCProto import *

     3

     4

LPC_STATUS={0xaa : "Started",

     5

            0x55 : "Stopped"}

     6

     7

class LPCAppProto(LPCProto):

     8

    def HandleTransaction(self, transaction):

     9

        self.TransactionLock.acquire()

    10

        try:

    11

            transaction.SetPseudoFile(self.serialPort)

    12

            # send command, wait ack (timeout)

    13

            transaction.SendCommand()

    14

            current_plc_status = transaction.GetCommandAck()

    15

            if current_plc_status is not None:

    16

                res = transaction.ExchangeData()

    17

            else:

    18

                raise LPCProtoError("controller did not answer as expected")

    19

        except Exception, e:

    20

            raise LPCProtoError("application mode transaction error : "+str(e))

    21

        finally:

    22

            self.TransactionLock.release()

    23

        return LPC_STATUS.get(current_plc_status,"Broken"), res

    24

    25

class LPCAppTransaction:

    26

    def __init__(self, command):

    27

        self.Command = command

    28

        self.pseudofile = None

    29

    30

    def SetPseudoFile(self, pseudofile):

    31

        self.pseudofile = pseudofile

    32

    33

    def SendCommand(self):

    34

        # send command thread

    35

        self.pseudofile.write(chr(self.Command))

    36

    37

    def GetCommandAck(self):

    38

        res = self.pseudofile.read(2)

    39

        if len(res) == 2:

    40

            comm_status, current_plc_status = map(ord, res)

    41

        else:

    42

            raise LPCProtoError("LPC transaction error - controller did not ack order")

    43

        # LPC returns command itself as an ack for command

    44

        if(comm_status == self.Command):

    45

            return current_plc_status

    46

        return None 

    47

    48

    def SendData(self, Data):

    49

        length = len(Data)

    50

        # transform length into a byte string

    51

        # we presuppose endianess of LPC same as PC

    52

        lengthstr = ctypes.string_at(ctypes.pointer(ctypes.c_int(length)),4)

    53

        buffer = lengthstr + Data

    54

        return self.pseudofile.write(buffer)

    55

    56

    def GetData(self):

    57

        lengthstr = self.pseudofile.read(4)

    58

        # transform a byte string into length 

    59

        length = ctypes.cast(ctypes.c_char_p(lengthstr), ctypes.POINTER(ctypes.c_int)).contents.value

    60

        return self.pseudofile.read(length)

    61

    62

    def ExchangeData(self): 

    63

        pass

    64

    65

class IDLETransaction(LPCAppTransaction):

    66

    def __init__(self):

    67

        LPCAppTransaction.__init__(self, 0x07)

    68

    ExchangeData = LPCAppTransaction.GetData

    69

    70

class STARTTransaction(LPCAppTransaction):

    71

    def __init__(self):

    72

        LPCAppTransaction.__init__(self, 0x01)

    73

    74

class STOPTransaction(LPCAppTransaction):

    75

    def __init__(self):

    76

        LPCAppTransaction.__init__(self, 0x02)

    77

    78

class RESETTransaction(LPCAppTransaction):

    79

    def __init__(self):

    80

        LPCAppTransaction.__init__(self, 0x03)

    81

    82

class SET_TRACE_VARIABLETransaction(LPCAppTransaction):

    83

    def __init__(self, data):

    84

        LPCAppTransaction.__init__(self, 0x04)

    85

        self.Data = data

    86

    def ExchangeData(self):

    87

        self.SendData(self.Data)

    88

    89

class GET_TRACE_VARIABLETransaction(LPCAppTransaction):

    90

    def __init__(self):

    91

        LPCAppTransaction.__init__(self, 0x05)

    92

    ExchangeData = LPCAppTransaction.GetData

    93

    94

class GET_PLCIDTransaction(LPCAppTransaction):

    95

    def __init__(self):

    96

        LPCAppTransaction.__init__(self, 0x07)

    97

    ExchangeData = LPCAppTransaction.GetData

    98

    99

class GET_LOGCOUNTSTransaction(LPCAppTransaction):

   100

    def __init__(self):

   101

        LPCAppTransaction.__init__(self, 0x0B)

   102

    ExchangeData = LPCAppTransaction.GetData

   103

   104

class GET_LOGMSGTransaction(LPCAppTransaction):

   105

    def __init__(self,level,msgid):

   106

        LPCAppTransaction.__init__(self, 0x0C)

   107

        msgidstr = ctypes.string_at(ctypes.pointer(ctypes.c_int(msgid)),4)

   108

        self.Data = chr(level)+msgidstr

   109

   110

    def ExchangeData(self):

   111

        self.SendData(self.Data)

   112

        return self.GetData()

   113

   114

if __name__ == "__main__":

   115

    __builtins__.BMZ_DBG = True

   116

    TestConnection = LPCAppProto(6,115200,2)

   117

#    TestConnection.HandleTransaction(GET_PLCIDTransaction())

   118

    TestConnection.HandleTransaction(STARTTransaction())

   119

#    TestConnection.HandleTransaction(SET_TRACE_VARIABLETransaction(

   120

#           "\x03\x00\x00\x00"*200))

   121

#    TestConnection.HandleTransaction(STARTTransaction())

   122

    while True:

   123

        TestConnection.HandleTransaction(SET_TRACE_VARIABLETransaction(

   124

           "\x01\x00\x00\x00"+

   125

           "\x04"+

   126

           "\x01\x02\x02\x04"+

   127

           "\x01\x00\x00\x00"+

   128

           "\x08"+

   129

           "\x01\x02\x02\x04"+

   130

           "\x01\x02\x02\x04"+

   131

           "\x01\x00\x00\x00"+

   132

           "\x04"+

   133

           "\x01\x02\x02\x04"))

   134

    #status,res = TestConnection.HandleTransaction(GET_TRACE_VARIABLETransaction())

   135

    #print len(res)

   136

    #print "GOT : ", map(hex, map(ord, res))

   137

    #TestConnection.HandleTransaction(STOPTransaction())