add comments

tools/demo.py

@@ -8,7 +8,10 @@ import time
 import math
 
 # Find a connected ODrive (this will block until you connect one)
-my_drive = odrive.core.find_any(printer=print)
+odrives = odrive.core.find_all(printer=print)
+odrives = list(odrives) #force eval of generator to test finding functions
+my_drive = odrives[0]
+# my_drive = odrive.core.find_any(printer=print)
 
 # The above call returns a python object with a dynamically generated type. The
 # type hierarchy will correspond to the endpoint list in `MotorControl/protocol.cpp`.
@@ -29,7 +32,7 @@ my_drive.motor0.set_pos_setpoint(0.0, 0.0, 0.0)
 
 # little sine wave to test
 t0 = time.monotonic()
-while True:
+while False:
     setpoint = 10000.0 * math.sin((time.monotonic() - t0)*2)
     print("goto " + str(int(setpoint)))
     my_drive.motor0.set_pos_setpoint(setpoint, 0.0, 0.0)
@@ -39,7 +42,7 @@ while True:
 # Some more things you can try:
 
 # Write to a read-only property:
-# my_drive.vbus_voltage = 5  # fails with `AttributeError: can't set attribute`
+my_drive.vbus_voltage = 11.0  # fails with `AttributeError: can't set attribute`
 
 # Assign an incompatible value:
 # my_drive.motor0.pos_setpoint = "I like trains"  # fails with `TypeError: expected value of type float`

tools/odrive/core.py

@@ -68,12 +68,16 @@ def call_remote_function(channel, trigger_id, arg_properties, *args):
         arg_properties[i].fset(None, args[i])
     channel.remote_endpoint_operation(trigger_id, None, True, 0)
 
+#Oskar: setattr_or_raise_if_undefined
 def raise_if_undefined(self, name, value):
     """
     If employed as an object's __setattr__ function, this function
     makes sure that an assignment to an undefined attribute doesn't
     create a new attribute but instead raises an exception
     """
+    #Oskar: hasattr internally calls fget to determine if the attribute exists,
+    # which unnessecarily creates bus traffic. We should try to solve this.
+    # Step-in on the hasattr line in the debugger to see this.
     if hasattr(self, name):
         object.__setattr__(self, name, value)
     else:
@@ -124,6 +128,8 @@ def create_property(name, json_data, channel, printer):
         printer("property {} has no specified ID".format(name))
         return None
 
+    #Oskar: Bug: json_data calls this "access", but we look for "mode".
+    # The default should probably be "r" anyway, it's safer I'd say.
     access_mode = json_data.get("mode", "rw")
     return SimpleDeviceProperty(channel, id_str, property_type,
                                 struct_format,
@@ -250,20 +256,30 @@ def find_usb_channels(vid_pid_pairs=odrive.util.USB_VID_PID_PAIRS, printer=nopri
                     continue
                 raise
 
+def find_dev_serial_ports(search_regex):
+    try:
+        return ['/dev/' + x for x in filter(re.compile(search_regex).search, os.listdir('/dev'))]
+    except FileNotFoundError:
+        return []
+
 def find_serial_channels(printer=noprint):
     """
     Scans for serial ports.
     Returns a generator of odrive.protocol.Channel objects.
     Not every returned object necessarily represents a compatible device.
     """
+
+    #Oskar: Why not just use this tool to find the available ports?
+    # https://pyserial.readthedocs.io/en/latest/tools.html#module-serial.tools.list_ports
+
     # Real serial ports or USB-Serial converters
-    linux_real_serial_ports = ['/dev/' + x for x in filter(re.compile(r'^ttyUSB').search, os.listdir('/dev'))]
+    linux_real_serial_ports = find_dev_serial_ports(r'^ttyUSB')
     windows_real_serial_ports = [ "COM1", "COM2", "COM3", "COM4" ]
 
     # Serial devices that are exposed by the platform
     # for the device's USB connection
-    linux_usb_serial_ports = ['/dev/' + x for x in filter(re.compile(r'^ttyACM').search, os.listdir('/dev'))]
-    macos_usb_serial_ports = ['/dev/' + x for x in filter(re.compile(r'^tty\.usbmodem').search, os.listdir('/dev'))]
+    linux_usb_serial_ports = find_dev_serial_ports(r'^ttyACM')
+    macos_usb_serial_ports = find_dev_serial_ports(r'^tty\.usbmodem')
 
     for port in linux_real_serial_ports + windows_real_serial_ports + linux_usb_serial_ports + macos_usb_serial_ports:
         try:

tools/odrive/protocol.py

@@ -56,6 +56,10 @@ class ChannelBrokenException(Exception):
 class DeviceInitException(Exception):
     pass
 
+#Oskar: I would just get rid of these "abstract classes",
+# I think just looking and seeing that the classes have
+# a process_packet or get_packet is enough.
+
 class StreamSource(object):
     pass
 
@@ -171,6 +175,7 @@ class Channel(PacketSink):
     _expected_acks = {}
 
     # Chose these parameters to be sensible for a specific transport layer
+    #Oskar: it's a timeout, not delay.
     _resend_delay = 5.0     # [s]
     _send_attempts = 5
 
@@ -203,11 +208,11 @@ class Channel(PacketSink):
 
         crc16 = calc_crc16(CRC16_INIT, packet)
         if (endpoint_id & 0x7fff == 0):
-            footer = PROTOCOL_VERSION
+            trailer = PROTOCOL_VERSION
         else:
-            footer = self._interface_definition_crc
-        #print("append footer " + footer)
-        packet = packet + struct.pack('<H', footer)
+            trailer = self._interface_definition_crc
+        #print("append trailer " + trailer)
+        packet = packet + struct.pack('<H', trailer)
 
         if (expect_ack):
             self._expected_acks[seq_no] = None

tools/test_communication.py

@@ -55,6 +55,9 @@ def print_usage():
 # that will leave that odrive variable in scope for the interactive session; just give the user some instructions
 # that they can then do stuff like odrive.[tabcomplete]
 
+# We can also make a function odrive.send_legacy_cmd(cmd_str), which is important for some features that
+# we haven't ported yet.
+
 def command_prompt_loop(device, history):
   """
   Presents the command prompt indefinitely until something goes wrong