标签: bacnet

我正在尝试剖析数据包,它封装了另一个类似于数据包的结构,称为"标记".结构看起来像这样

+---------+
|Ether    |
+---------+
|IP       |                   a tag
+---------+
|UDP      |                +------------+
+---------+                |tagNumber   |
|BVLC     |                +------------+
+---------+                |tagClass    |
|NPDU     |                +------------+
+---------+           +-+  |LVT field   |
|APDU     |           |    +------------+
|  +------+--+        |    |            |
|  |Tag 1    | <------+    |  data      |
|  +---------+             |            |
|  |Tag 2    |             +------------+
|  +---------+
|  |Tag n    |
+------------+

为此,我创建了一个派生自现有的类PacketListField,如下所示:

class TagListField(PacketListField):
    def __init__(self):
        PacketListField.__init__(
            self,
            "tags",
            [],
            guessBACNetTagClass,

引用guessBACNetTagClass的函数返回解析标记所需的正确类.

BACNetTagClasses = …

我有一项任务是通过BACnet TCP/IP从Trane Tracer summitBCU通信和读取BACnet对象列表及其属性.但是,我不知道从BCU获取BACnet对象列表的BACnet服务.每个人都可以教我如何做到这一点!