Knowledge Base
Showing results for 
Search instead for 
Did you mean: 

BACnet MSTP Sniffer Tool


BACnet MSTP Sniffer Tool


Any Bacnet MSTP Network


The BACnet MSTP Sniffer tool provides the ability to analyze data communications between devices anytime issues are suspected on the network.


The MSTP Tool was created by Steve Karg and is free to download. For further information about Steve Karg or BACnet MSTP tool it is available at .  To download a copy of the BACnet MSTP tool and instructions click here .

To capture data follow these steps:

  1. Unzip file
  2. Open command prompt  with window pointing at location of mstpcap.exe file.  For example:  c:\MSTP Tool>
  3. Daisy chain RS-485 adapter to trunk or connect Roam I/A to jack on MNB device.
  4. Command syntax is as follows:  mstpcap comx baudrate# do not type baudrate just speed.
  5. Control C to stop


If Using Roam I/A it requires highest baudrate available on the interface.

ROAM I/A Serial port

  • mstpcap comx 115200

If using Roam I/A Blue tooth

  • mstpcap comx 76800

If using an RS-485 adapter it will not support 76,800. This is a PC hardware limitation not a software limitation for further instructions on how to use baudrate 76,800 consult text file titled mstpcap.txt or Steve Karg's website: . 


  • mstpcap comx baudrate speed

The capture file can be analyzed with WireShark Protocol Analyzer.  WireShark software is available at:

Tags (1)
Version history
Revision #:
1 of 1
Last update:
2 weeks ago
Updated by: