Make interface optional. Correct the documentation

README.md

@@ -28,7 +28,7 @@ You can instantiate a CaroA04 object and start it to communicate with the device
 from caroa04 import CaroA04
 
 caro = CaroA04()
-caro.start(0xE0, 'pcan', 250000, 'PCAN_USBBUS1')  # start communication
+caro.start(0xE0, 'pcan', 250000, 'PCAN_USBBUS1')  # start communication with device node ID 0xE0
 
 caro.do1.phys = True  # set do1 state to True
 print(caro.do1.phys)  # read do1 state
@@ -40,7 +40,7 @@ caro.bitrate.phys = 500000  # set different baudrate (will require device power
 print(caro.node_id.phys)  # read current address code
 caro.node_id.phys = 0xE1  # set address code (will require device power cycle)
 
-caro.shutdown()  # free the bus
+caro.stop()  # free the bus
 ```
 
 In order to share the bus with other participants, you can assign the bus attribute of the CaroA04 object before starting it.
@@ -58,8 +58,8 @@ caro = CaroA04()
 caro.bus = nw.bus  # use the bus already started by canopen
 nw.notifier.add_listener(caro.listener)  # add listener so that we can receive messages
 
-caro.start(0xE0, 'pcan')  # start communication
-caro.shutdown()  # free the bus
+caro.start(0xE0)  # start communication with node ID 0xE0
+caro.stop()  # free the bus
 ```
 
 ## Features

README.rst

@@ -46,7 +46,7 @@ You can instantiate a CaroA04 object and start it to communicate with the device
     from caroa04 import CaroA04
 
     caro = CaroA04()
-    caro.start(0xE0, 'pcan', 250000, 'PCAN_USBBUS1')  # start communication
+    caro.start(0xE0, 'pcan', 250000, 'PCAN_USBBUS1')  # start communication with device node ID 0xE0
 
     caro.do1.phys = True  # set do1 state to True
     print(caro.do1.phys)  # read do1 state
@@ -58,7 +58,7 @@ You can instantiate a CaroA04 object and start it to communicate with the device
     print(caro.node_id.phys)  # read current address code
     caro.node_id.phys = 0xE1  # set address code (will require device power cycle)
 
-    caro.shutdown()  # free the bus
+    caro.stop()  # free the bus
 
 ..
 
@@ -78,8 +78,8 @@ You should simply then add CaroA04's listener to the existing bus' notifier.
     caro.bus = nw.bus  # use the bus already started by canopen
     nw.notifier.add_listener(caro.listener)  # add listener so that we can receive messages
 
-    caro.start(0xE0, 'pcan')  # start communication
-    caro.shutdown()  # free the bus
+    caro.start(0xE0)  # start communication with node ID 0xE0
+    caro.stop()  # free the bus
 
 ..
 

src/caroa04/caroa04.py

@@ -105,7 +105,7 @@ def __init__(self):
             self.node_id
         )
 
-    def start(self, node_id, interface, bitrate=None, channel=None):
+    def start(self, node_id, interface=None, bitrate=None, channel=None):
         """
         Start the communication.
         :param node_id: node ID (or address code) of the device
@@ -163,3 +163,4 @@ def stop(self):
     caro.do1.phys = True
     print(caro.do1.phys)
     caro.do1.phys = False
+    caro.stop()

tests/test_caroa04.py

@@ -85,7 +85,7 @@ def stop(self):
             self.bus = None
 
 
-class TestVirtualCanIoExp1:
+class TestVirtualCaroA04:
     @pytest.fixture(scope="class")
     def caro(self):
         return CaroA04()