diff zb.py @ 11:75f785a09e2e

Add license. Split test stuff into a separate file. Fix some bugs.. - Default frame ID to 1 so we get status replies by default. - Correct address generation routine for TX packets. Add doc strings and epydoc variable comments.
author darius@Inchoate
date Tue, 13 Jan 2009 12:14:13 +1030
parents 4c91fdfc862e
children 729f2393f296
line wrap: on
line diff
--- a/zb.py	Wed Nov 07 17:10:08 2007 +1030
+++ b/zb.py	Tue Jan 13 12:14:13 2009 +1030
@@ -1,25 +1,77 @@
-import serial, inspect, time
+#
+# Code to talk to MaxStream ZigBee modules in API (no escaped
+# characters)
+#
+# Copyright (c) 2009
+#      Daniel O'Connor <darius@dons.net.au>.  All rights reserved.
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions
+# are met:
+# 1. Redistributions of source code must retain the above copyright
+#    notice, this list of conditions and the following disclaimer.
+# 2. Redistributions in binary form must reproduce the above copyright
+#    notice, this list of conditions and the following disclaimer in the
+#    documentation and/or other materials provided with the distribution.
+#
+# THIS SOFTWARE IS PROVIDED BY AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+# ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+# ARE DISCLAIMED.  IN NO EVENT SHALL AUTHOR OR CONTRIBUTORS BE LIABLE
+# FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+# DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+# OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+# HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+# LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+# OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+# SUCH DAMAGE.
+#
+"""MaxStream ZigBee module API interface
+
+This code expects the module to be in API mode 1 (no escape
+characters), ie you have done something like..
++++
+ATAP=1
+ATWR
+ATCN
+
+See here for details
+http://www.digi.com/products/wireless/point-multipoint/xbee-series1-moduledocs.jsp
+"""
+
+import inspect
 
 def easyord(i):
+    """Helper function to return the ordinal of a string, or just the
+passed in value"""
     if (type(i) != type(str())):
         return i
     else:
         return ord(i)
 
 class PktBase(object):
+    """Base class for all packet types"""
     PKT_MAXLEN = 2 ** 16
+    PKT_TYPE = None
     
     def __init__(self):
-        print "Constructing " + self.__class__.__name__
+        #print "Constructing " + self.__class__.__name__
+        pass
+    
+    def Encapsulate(self):
+        """Encapsulate the packet"""
+        return Packets.Encapsulate([self.PKT_TYPE] + self.data)
 
-    def Encapsulate(self):
-        return Packets.Encapsulate([self.PKT_TYPE] + self.data)
+    def Pack(self):
+        """Return string version of encapsulated packet"""
+        return reduce(lambda x, y: str(x) + str(y), self.Encapsulate())
 
     def resize(self, dlen):
         """Ensure the data list can hold at least len elements (0 fill)"""
         if (len(self._data) < dlen):
             self._data = (self._data + [0] * dlen)[0:dlen]
 
+    @staticmethod
     def _checklist(list, min = 0, max = 255, maxlen = None):
         if (maxlen != None and len(list) > maxlen):
             raise ValueError("must have %d elements" % (maxlen))
@@ -28,31 +80,35 @@
             if (easyord(list[i]) < min or easyord(list[i]) > max):
                 raise ValueError("element %d (= %d) out of range must be between %d and %d inclusive" %
                                  (i, ord(list[i]), min, max))
-    _checklist = staticmethod(_checklist)
 
 class TXPkts(PktBase):
     """Base class for all packets that go to the module"""
 
+    def __init__(self):
+        # Frame ID of 0 will prevent TX status pakets being sent
+        self._frameid = 1
+        
     def setframeid(self, value):
         if (value < 0 or value > 255):
             raise ValueError("FrameID must be 0-255")
         self._frameid = value
     frameid =  property(lambda s: s._frameid, setframeid)
     
+class AT_Cmd(TXPkts):
+    """AT command packet"""
     
-class AT_Cmd(TXPkts):
     PKT_TYPE = 0x08
     PKT_DESC = "AT Command"
 
     def __init__(self, cmd = None, cmdarg = None):
+        self.frameid = 1 # XXX: why do I need to dupe this?
+        self.cmdarg = []
+
         super(AT_Cmd, self).__init__()
         if (cmd != None):
             self.cmd = cmd
         if (cmdarg != None):
             self.cmdarg = cmdarg
-
-        self.frameid = 0
-        self.cmdarg = []
         
     def setcmd(self, value):
         if (len(value) != 2):
@@ -71,10 +127,14 @@
     data = property(getdata)
 
 class AT_Cmd_Queue(AT_Cmd):
+    """Queued AT command packet"""
+    
     PKT_TYPE = 0x09
     PKT_DESC = "AT Command (queued)"
 
 class AT_Response(PktBase):
+    """Response from an AT command packet"""
+    
     PKT_TYPE = 0x88
     PKT_DESC = "AT Command response"
     frameid = property(lambda s: s._data[0], None)
@@ -82,42 +142,71 @@
     statusOK = property(lambda s: s._data[3] == 0, None)
     payload = property(lambda s: s._data[4:], None)
 
+    def __init__(self, data = []):
+        super(AT_Response, self).__init__()
+        self._data = data
+    
 class Modem_Status(PktBase):
     PKT_TYPE = 0x8a
     PKT_DESC = "Modem Status"
 
 class RX_16_Bit(PktBase):
+    """RX packet from a remote module (16 bit)"""
     PKT_TYPE = 0x81
     PKT_DESC = "RX Packet: 16 bit address"
     ADDR_SIZE = 2
+    ADRBCASTMSK = 0x01
+    PANBCASTMSK = 0x02
     
     def __init__(self, data = []):
         super(RX_16_Bit, self).__init__()
         self._data = data
-
+    
     def __str__(self):
-        return "0x%0*x (%ddBm) -> %s" % (self.ADDR_SIZE * 2, self.sender,
-                                         self.rssi, str(self.payload))
-        
+        return "RX_%d_Bit 0x%0*x (%ddBm) -> %s" % (self.ADDR_SIZE * 8, self.ADDR_SIZE * 2,
+                                                   self.sender, self.rssi, self.payloadstr)
     def getsender(self):
         value = 0
+        # Done this way so we can reuse the code for the 64 bit version
         for i, j in zip(reversed(range(self.ADDR_SIZE)), range(0, self.ADDR_SIZE * 8, 8)):
             value |= self._data[i] << j
         return value
+    #: Source module address
     sender = property(getsender, None)
 
+    def isAdrBcast(self):
+        """Is this an address broadcast packet?"""
+        return self.flags & self.ADRBCASTMSK
+
+    def isPanBcast(self):
+        """Is this an PAN broadcast packet?"""
+        return self.flags & self.PANBCASTMSK
+    
+    #: RX signal strength (dBm)
     rssi = property(lambda s: -1 * s._data[s.ADDR_SIZE], None)
 
+    #: Return flag byte
     flags = property(lambda s: s._data[s.ADDR_SIZE + 1], None)
 
+    #: Payload (list of ords)
     payload = property(lambda s: s._data[s.ADDR_SIZE + 2:], None)
-                       
+
+    #: String version of payload
+    def payloadstr(self):
+        return reduce(lambda a, b: a + chr(b), self.payload, "")
+    payloadstr = property(payloadstr, None)
+    
+    
 class RX_64_Bit(RX_16_Bit):
     PKT_TYPE = 0x80
     PKT_DESC = "RX Packet: 64 bit address"
     ADDR_SIZE = 8
 
 class RXIO_16_Bit(RX_16_Bit):
+    """RX I/O packet from remote module (16 bit).
+
+This is sent when a remote module is configured to send data based on its IO or DAC pins
+"""
     PKT_TYPE = 0x83
     PKT_DESC = "RXIO Packet: 16 bit address"
 
@@ -151,33 +240,45 @@
     ADDR_SIZE = 8
     
 class TX_16_Bit(TXPkts):
+    """Transmit to a 16 bit destination"""
     PKT_TYPE = 0x01
     PKT_DESC = "TX Packet: 16 bit address"
     ADDR_SIZE = 2
+    #: Flag to disable ACK
     FLG_DISABLE_ACK = 0x01
+    #: Send to broadcast PAN ID
     FLG_BCAST_PANID = 0x04
+    #: Maximum size payload we can send
     PKT_MAX_PAYLOAD = 100
     
     def __init__(self, *args):
-        if (len(args) == 1):
+        """Takes 0 to 2 arguments. First is the recipient, the second is the payload (string)"""
+        self._flags = 0
+        self.payload = []
+
+        if len(args) == 0:
+            pass
+        if len(args) == 1:
             super(TX_16_Bit, self).__init__()
             self.recipient = args[0]
-        elif (len(args) == 2):
-            super(TX_16_Bit, self).__init__([])
+        elif len(args) == 2:
+            super(TX_16_Bit, self).__init__()
             self.recipient = args[0]
             self.payload = args[1]
         else:
-            raise TypeError("__init__ takes 1 list of ordinals or 2 strings")
+            raise TypeError("incorrect number of arguments");
 
-        self.frameid = 0
-        self.flags = 0
-        self.payload = []
-        
+    def __str__(self):
+        return "TX_%d_Bit 0x%0*x <- %s" % (self.ADDR_SIZE * 8, self.ADDR_SIZE * 2, self.recipient,
+                                           self.payload)
+    
     def setrecipient(self, value):
         if (value < 0 or value > 2 ** (self.ADDR_SIZE * 8)):
             raise ValueError("value out of range must be between 0 and %d" % (2 ** self.ADDR_SIZE))
         
         self._recipient = value
+
+    """Destination address of the packet"""
     recipient = property(lambda s: s._recipient, setrecipient)
 
     def setflags(self, value):
@@ -192,9 +293,13 @@
         self._payload = value
     payload = property(lambda s: s._payload, setpayload)
 
+    def payloadstr(self):
+        return reduce(lambda a, b: a + chr(b), self.payload, "")
+    payloadstr = property(payloadstr, None)
+
     def getdata(self):
         data = [self.frameid]
-        for i, j in zip(reversed(range(self.ADDR_SIZE)), range(0, self.ADDR_SIZE * 8, 8)):
+        for i, j in zip(reversed(range(self.ADDR_SIZE)), reversed(range(0, self.ADDR_SIZE * 8, 8))):
             data.append((self.recipient & (0xff << j)) >> j)
         data.append(self.flags)
         data.extend(map(easyord, self.payload))
@@ -213,11 +318,18 @@
     frameid = property(lambda s: s._data[0], None)
     status = property(lambda s: s._data[1], None)
     statusMsg = property(lambda s: s.statusTxt[s._data[1]], None)
-    
+
+    def __init__(self, data = []):
+        super(TX_Status, self).__init__()
+        self._data = data
+                 
 class Packets(object):
+    """Packet parsing class (misnamed)"""
     PKT_CLASSES = None
-    
+
+    @classmethod
     def Build(self, data):
+        """Build a packet from data"""
         if (self.PKT_CLASSES == None):
             m = inspect.getmodule(self)
             # Generate list of objects from their names
@@ -230,20 +342,21 @@
             
         for p in self.PKT_CLASSES:
             if (p.PKT_TYPE == data[0]):
+                #print "Matched " + str(p.PKT_TYPE)
                 return(p(data[1:]))
 
         raise ValueError("Unknown packet type 0x%02x" % (data[0]))
-    Build = classmethod(Build)
 
+    @staticmethod
     def Encapsulate(data):
+        """Encapsulate a packet so it can be sent to the module. Calculates checksum etc.."""
         pktsum = reduce(lambda x, y: x + y, data) & 0xff
         pkt = [0x7e] + [len(data) >> 8] + [len(data) & 0xff] + data + [0xff - pktsum]
         return(map(chr, pkt))
     
-    Encapsulate = staticmethod(Encapsulate)
-
     def __init__(self, s = None):
-        print str(inspect.getmodule(self))
+        """Init class, if s is passed in it is used for reading & writing data"""
+        #print str(inspect.getmodule(self))
         self.buffer = []
         self.state = 'init'
         self.packets = []
@@ -256,27 +369,38 @@
         self.rx_cnt = 0 # Packet count
         
         self.pktq = []
-        self.s = s
+        self.s = s      # Output handle for convenience methods
         
     def writedata(self, data):
+        """Convenience method to write data"""
         self.s.write("".join(map(str, data)))
                 
     def getdata(self):
+        """Read data until nothing is available (assumes non-blocking) and process it"""
         l = []
-        while (1):
+        while 1:
             a = self.s.read()
-            if (a == ''):
+            if a == '':
                 break
             l.append(ord(a))
     
         return self.process(l)
     
+    def processstr(self, data):
+        """Process a string of data"""
+        return self.process(map(ord, data))
+    
     def process(self, data):
+        """Process (ordinal) data through the state machine.
+
+Returns the number of packets in the queue when finished. Updates
+various internal counters too.
+"""
         pktcount = 0
         for d in data:
             if (self.state == 'init'):
                 if (d != 0x7e):
-                    print "Framing error, got 0x%02x, expected 0x7e" % (d)
+                    print "Framing error, got 0x%02x, expected 0x7e" % d
                     self.fr_err += 1
                     continue
                 
@@ -302,7 +426,7 @@
                     print "Checksum error, got 0x%02x, expected 0x%02x" % \
                           (rxcksum, 0xff - pktsum)
                 else:
-                    print "Got a packet - " + str(self.buffer)
+                    #print "Got a packet - " + str(self.buffer)
                     p = Packets.Build(self.buffer)
                     self.pktq.append(p)
                     self.buffer = []
@@ -314,49 +438,3 @@
         
         return pktcount
 
-def polldev():
-    while (1):
-        foo = up.getdata()
-        for p in up.pktq:
-            print p
-
-        if (foo == 0):
-            time.sleep(0.1)
-
-#for c in dir():
-#    if (issubclass(c, PktBase)):
-#        print ..
-
-try:
-    s = serial.Serial(port='/dev/cuaU0', baudrate=9600, bytesize=8, parity='N', \
-                      stopbits=1, rtscts=0)
-    # Non-blocking
-    s.timeout = 0
-    #s.write('+++')
-    #s.readline(eol='\r')
-except serial.serialutil.SerialException, e:
-    print "Can't open serial port - " + str(e)
-    s = None
-    
-# 0x0001 (-36dBm) -> 1 samples, mask 0x000f, DIO - 0x00f
-goodtest = [126, 0, 10, 131, 0, 1, 36, 0, 1, 0, 15, 0, 15, 56]
-
-# Checksum error
-badtest = [126, 0, 10, 131, 0, 1, 36, 0, 1, 0, 15, 0, 14, 56]
-
-#0x0005 (-36dBm) -> 1 samples, mask 0x020e, DIO - 0x00e, ADC0 - 0x3ff
-adctest = [126, 0, 12, 131, 0, 5, 36, 0, 1, 2, 14, 0, 14, 3, 255, 50]
-
-# Exception
-badpkttypetest = [126, 0, 3, 10, 86, 76, 83]
-
-# Frame ID = 0, Cmd = 'VL', Status = OK, Value = 'VL Result'
-atreply = [126, 0, 14, 136, 0, 86, 76, 0, 86, 76, 32, 82, 101, 115, 117, 108, 116, 148]
-
-up = Packets(s)
-up.process(goodtest)
-up.process(badtest)
-up.process(adctest)
-print up.pktq.pop(0)
-print up.pktq.pop(0)
-