Add SYNC support.

Author: Christian Sandberg

canopen/emcy.py

@@ -32,6 +32,8 @@ def __init__(self):
         self.log = []
 
     def on_emcy(self, can_id, data, timestamp):
+        if can_id == 0x80:
+            return
         code, register, data = EMCY_STRUCT.unpack(data)
         if code & 0xFF == 0:
             entry = ErrorReset(code, register, data, timestamp)

canopen/network.py

@@ -5,6 +5,7 @@
 import can
 
 from .node import Node
+from .sync import SyncProducer
 
 
 logger = logging.getLogger(__name__)
@@ -18,6 +19,7 @@ def __init__(self):
         self.notifier = None
         self.nodes = []
         self.send_lock = threading.Lock()
+        self.sync = SyncProducer(self)
         # NMT to all nodes
         #self.nmt = NmtNode(0)
 

canopen/pdo.py

@@ -24,8 +24,10 @@ def __init__(self, parent):
     def on_message(self, can_id, data, timestamp):
         for pdo_map in self.tx.values():
             if pdo_map.cob_id == can_id:
-                pdo_map.data = data
-                pdo_map.timestamp = timestamp
+                with pdo_map.receive_condition:
+                    pdo_map.data = data
+                    pdo_map.timestamp = timestamp
+                    pdo_map.receive_condition.notify_all()
 
     def get_by_name(self, name):
         for pdo_maps in (self.rx, self.tx):
@@ -53,11 +55,10 @@ def export(self, filename):
                     continue
                 frame = canmatrix.Frame("PDO_0x%X" % pdo_map.cob_id,
                                         Id=pdo_map.cob_id,
-                                        dlc=len(pdo_map.data),
                                         extended=0)
                 for var in pdo_map.map:
                     is_signed = var.od.data_type in objectdictionary.SIGNED_TYPES
-                    if_float = var.od.data_type == objectdictionary.REAL32
+                    is_float = var.od.data_type == objectdictionary.REAL32
                     min_value = var.od.min
                     max_value = var.od.max
                     if min_value is not None:
@@ -68,14 +69,15 @@ def export(self, filename):
                                               startBit=var.offset,
                                               signalSize=len(var.od),
                                               is_signed=is_signed,
-                                              is_float=if_float,
+                                              is_float=is_float,
                                               factor=var.od.factor,
                                               min=min_value,
                                               max=max_value,
                                               unit=var.od.unit)
                     for value, desc in var.od.value_descriptions.items():
                         signal.addValues(value, desc)
                     frame.addSignal(signal)
+                frame.calcDLC()
                 db._fl.addFrame(frame)
         exportdbc.exportDbc(db, filename)
 
@@ -118,6 +120,7 @@ def __init__(self, pdo_node, com_index, map_index):
         self.timestamp = None
         self.period = None
         self.transmit_thread = None
+        self.receive_condition = threading.Condition()
         self.stop_event = threading.Event()
 
     def __getitem__(self, key):
@@ -251,6 +254,12 @@ def stop(self):
             self.transmit_thread.join(2)
             self.transmit_thread = None
 
+    def wait_for_reception(self, timeout=10):
+        with self.receive_condition:
+            self.timestamp = None
+            self.receive_condition.wait(timeout)
+        return self.timestamp
+
     def _periodic_transmit(self):
         while not self.stop_event.is_set():
             start = time.time()

canopen/sync.py

@@ -0,0 +1,40 @@
+import time
+import threading
+
+
+class SyncProducer(object):
+
+    def __init__(self, network):
+        self.network = network
+        self.period = None
+        self.transmit_thread = None
+        self.stop_event = threading.Event()
+
+    def transmit(self):
+        self.network.send_message(0x80, [])
+
+    def start(self, period=None):
+        """Start periodic transmission of SYNC message in a background thread."""
+        if period is not None:
+            self.period = period
+
+        if not self.period:
+            raise ValueError("A valid transmission period has not been given")
+
+        if not self.transmit_thread or not self.transmit_thread.is_alive():
+            self.stop_event.clear()
+            self.transmit_thread = threading.Thread(target=self._periodic_transmit)
+            self.transmit_thread.daemon = True
+            self.transmit_thread.start()
+
+    def stop(self):
+        self.stop_event.set()
+        if self.transmit_thread:
+            self.transmit_thread.join(2)
+            self.transmit_thread = None
+
+    def _periodic_transmit(self):
+        while not self.stop_event.is_set():
+            start = time.time()
+            self.transmit()
+            time.sleep(self.period - (time.time() - start))

setup.py

@@ -1,6 +1,6 @@
 from setuptools import setup, find_packages
 
-__version__ = "0.3.0.dev3"
+__version__ = "0.3.0.dev4"
 
 setup(
     name="canopen",