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BACnet Object Identifier Encoder / Decoder

That 32-bit number in your packet capture is an object type and an instance packed together. Here's how to split it.

Free tool · BAS Communication — A Field Reference

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How to use it

  1. In a Wireshark capture or a raw read, an object identifier appears as a single 32-bit number.
  2. Paste it in Decode mode to get the object type and instance.
  3. Or use Encode mode to build the identifier when a tool asks for one value rather than two fields.
  4. The maths: identifier = object type × 4,194,304 + instance.

Background reading: Chapter 3 — BACnet objects →

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More where this came from

These tools come out of the book — a field reference for BACnet, Modbus, LonWorks, OPC UA and the diagnostic method that works across all of them.

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