JoelBender
TypeError: unsupported operand type(s) for -: 'float' and 'NoneType'` in cov.py
I overwrite a presentValue of an analogValueObject in my COV application. I get the following error after a thousand or so overwrites:
Traceback (most recent call last):
File "/usr/local/lib/python3.9/threading.py", line 973, in _bootstrap_inner
self.run()
File "/code/./main.py", line 230, in run
bacnet_object.WriteProperty("presentValue", value)
File "/usr/local/lib/python3.9/site-packages/bacpypes/object.py", line 620, in WriteProperty
return prop.WriteProperty(self, value, arrayIndex, priority, direct)
File "/usr/local/lib/python3.9/site-packages/bacpypes/object.py", line 363, in WriteProperty
fn(old_value, value)
File "/usr/local/lib/python3.9/site-packages/bacpypes/service/detect.py", line 45, in property_change
trigger = self.filter(old_value, new_value)
File "/usr/local/lib/python3.9/site-packages/bacpypes/service/cov.py", line 317, in present_value_filter
value_changed = (new_value <= (self.previous_reported_value - self.obj.covIncrement))
TypeError: unsupported operand type(s) for -: 'float' and 'NoneType'
When I restart the service, a lot of messages come in in quick succession, so it happens almost immediately. The rate of overwrites slows down to 6 per minute after a while.
I don't see anything from the written values that would indicate anything:
Writing 6.43 to <main.WritableAnalogValueObject object at 0x7f41eadc3130> Writing 5.31 to <main.WritableAnalogValueObject object at 0x7f41eadc3130> Writing 2.89 to <main.WritableAnalogValueObject object at 0x7f41eadc3130> Writing 7.14 to <main.WritableAnalogValueObject object at 0x7f41eadc3130> Writing 3.94 to <main.WritableAnalogValueObject object at 0x7f41eadc3130> Writing 3.18 to <main.WritableAnalogValueObject object at 0x7f41eadc3130> Writing 0.07 to <main.WritableAnalogValueObject object at 0x7f41eadc3130> Writing 8.87 to <main.WritableAnalogValueObject object at 0x7f41eadc3130> Writing 4.87 to <main.WritableAnalogValueObject object at 0x7f41eadc3130> Writing 1.87 to <main.WritableAnalogValueObject object at 0x7f41eadc3130> Writing 1.78 to <main.WritableAnalogValueObject object at 0x7f41eadc3130> Writing 7.13 to <main.WritableAnalogValueObject object at 0x7f41eadc3130> Writing 4.85 to <main.WritableAnalogValueObject object at 0x7f41eadc3130> unsupported operand type(s) for -: 'float' and 'NoneType' Writing 4.84 to <main.WritableAnalogValueObject object at 0x7f41eadc3130> unsupported operand type(s) for -: 'float' and 'NoneType' Writing 7.27 to <main.WritableAnalogValueObject object at 0x7f41eadc3130> unsupported operand type(s) for -: 'float' and 'NoneType' Writing 4.75 to <main.WritableAnalogValueObject object at 0x7f41eadc3130> unsupported operand type(s) for -: 'float' and 'NoneType' Writing 6.3 to <main.WritableAnalogValueObject object at 0x7f41eadc3130> unsupported operand type(s) for -: 'float' and 'NoneType' Writing 3.56 to <main.WritableAnalogValueObject object at 0x7f41eadc3130> unsupported operand type(s) for -: 'float' and 'NoneType' Writing 6.95 to <main.WritableAnalogValueObject object at 0x7f41eadc3130> unsupported operand type(s) for -: 'float' and 'NoneType' Writing 6.94 to <main.WritableAnalogValueObject object at 0x7f41eadc3130>
This has been tested with covIncrement=1.0 and without specifying one.
The error seems to disappear when I set the covIncrement to such a low value, that the notification is always triggered.
It would seem there is some tracking of what was previously reported that is getting cleared. Is this code using threads? I'm going to try and reproduce this error.
