Device Services

class WhoIsIAmServices(Capability)

This class provides the capability to initiate and respond to device-address-binding PDUs.

do_WhoIsRequest(apdu)

Parameters:apdu (WhoIsRequest) – Who-Is Request from the network

See Clause 16.10.1 for the parameters to this service.

do_IAmRequest(apdu)

Parameters:apdu (IAmRequest) – I-Am Request from the network

See Clause 16.10.3 for the parameters to this service.

who_is(self, low_limit=None, high_limit=None, address=None)

Parameters:

• low_limit (Unsigned) – optional low limit
• high_limit (Unsigned) – optional high limit
• address (Address) – optional destination, defaults to a global broadcast

This is a utility function that makes it simpler to generate a WhoIsRequest.

i_am(self, address=None)

Parameters:address (Address) – optional destination, defaults to a global broadcast

This is a utility function that makes it simpler to generate an IAmRequest with the contents of the local device object.

class WhoHasIHaveServices(Capability)

This class provides the capability to initiate and respond to device and object binding PDU’s.

do_WhoHasRequest(apdu)

Parameters:apdu (WhoHasRequest) – Who-Has Request from the network

See Clause 16.9.1 for the parameters to this service.

do_IHaveRequest(apdu)

Parameters:apdu (IHaveRequest) – I-Have Request from the network

See Clause 16.9.3 for the parameters to this service.

who_has(thing, address=None)

Parameters:

• thing – object identifier or object name
• address (Address) – optional destination, defaults to a global broadcast

Not implemented.

i_have(thing, address=None)

Parameters:

• thing – object identifier or object name
• address (Address) – optional destination, defaults to a global broadcast

This is a utility function that makes it simpler to generate an IHaveRequest given an object.

Support Classes

There are a few support classes in this module that make it simpler to build the most common BACnet devices.

class CurrentDateProperty(Property)

This class is a specialized readonly property that always returns the current date as provided by the operating system.

ReadProperty(self, obj, arrayIndex=None)

Returns the current date as a 4-item tuple consistent with the Python implementation of the Date primitive value.

WriteProperty(self, obj, value, arrayIndex=None, priority=None)

Object instances of this class are readonly, so this method raises a writeAccessDenied error.

class CurrentTimeProperty(Property)

This class is a specialized readonly property that always returns the current local time as provided by the operating system.

ReadProperty(self, obj, arrayIndex=None)

Returns the current date as a 4-item tuple consistent with the Python implementation of the Time primitive value.

WriteProperty(self, obj, value, arrayIndex=None, priority=None)

Object instances of this class are readonly, so this method raises a writeAccessDenied error.

class LocalDeviceObject(DeviceObject)

The LocalDeviceObject is an implementation of a DeviceObject that provides default implementations for common properties and behaviors of a BACnet device. It has default values for communications properties, returning the local date and time, and the objectList property for presenting a list of the objects in the device.