added getter for MESSAGE_GET_VALUES message type

pyvesc/messages/getters.py

@@ -0,0 +1,29 @@
+from pyvesc.messages.base import VESCMessage
+
+class GetValues(metaclass=VESCMessage):
+    """ Gets internal sensor data
+    """
+    id = 4
+    # When sending the request for this info, a blank ID must be sent
+    #    fields = []
+    fields = [
+            ('temp_mos1', 'e'),
+            ('temp_mos2', 'e'),
+            ('temp_mos3', 'e'),
+            ('temp_mos4', 'e'),
+            ('temp_mos5', 'e'),
+            ('temp_mos6', 'e'),
+            ('temp_pcb',  'e'),
+            ('current_motor', 'f'),
+            ('current_in',  'f'),
+            ('duty_now',    'e'),
+            ('rpm',         'f'),
+            ('v_in',        'e'),
+            ('amp_hours',   'f'),
+            ('amp_hours_charged', 'f'),
+            ('watt_hours',  'f'),
+            ('watt_hours_charged', 'f'),
+            ('tachometer', 'l'),
+            ('tachometer_abs', 'l'),
+            ('mc_fault_code', 'c')
+    ]