226 lines
9.0 KiB
Plaintext
226 lines
9.0 KiB
Plaintext
BACnet MS/TP Capture Tool
|
|
|
|
This tool captures BACnet MS/TP packets on an RS485 serial interface,
|
|
and saves the packets to a file in Wireshark PCAP format for
|
|
the BACnet MS/TP dissector to read. The filename has a date and time
|
|
code in it, and will contain up to 65535 packets. A new file
|
|
will be created at each 65535 packet interval. The tool can
|
|
be stopped by using Control-C. The tool can also pipe its output
|
|
to Wireshark to be monitored in real-time.
|
|
|
|
Here is a sample of the tool running (use CTRL-C to quit):
|
|
D:\code\bacnet-stack>bin\mstpcap.exe com54 38400
|
|
Adjusted interface name to \\.\COM54
|
|
mstpcap: Using \\.\COM54 for capture at 38400 bps.
|
|
mstpcap: saving capture to mstp_20110413134119.cap
|
|
1156 packets
|
|
==== MS/TP Frame Counts ====
|
|
MAC Device Tokens PFM RPFM DER Postpd DNER TestReq TestRsp
|
|
0 - 188 4 0 0 0 0 0 0
|
|
2 - 189 0 0 0 0 0 0 0
|
|
3 - 189 9 0 0 0 0 0 0
|
|
7 - 189 60 0 0 0 0 0 0
|
|
35 - 188 140 0 0 0 0 0 0
|
|
Node Count: 5
|
|
|
|
==== MS/TP Usage and Timing Maximums ====
|
|
MAC MaxMstr Retries Npoll Self Treply Tusage Trpfm Tder Tpostpd
|
|
0 1 0 52 0 11 24 0 0 0
|
|
2 0 0 0 0 23 0 0 0 0
|
|
3 6 0 50 0 5 100 0 0 0
|
|
7 34 0 52 0 5 34 0 0 0
|
|
35 127 0 50 0 6 63 0 0 0
|
|
Node Count: 5
|
|
Invalid Frame Count: 0
|
|
|
|
The files that are captured can also be scanned to give some statistics:
|
|
D:\code\bacnet-stack>bin\mstpcap.exe --scan mstp_20110413134119.cap
|
|
Scanning mstp_20110413134119.cap
|
|
1156 packets
|
|
==== MS/TP Frame Counts ====
|
|
MAC Device Tokens PFM RPFM DER Postpd DNER TestReq TestRsp
|
|
0 - 188 4 0 0 0 0 0 0
|
|
2 - 189 0 0 0 0 0 0 0
|
|
3 - 189 9 0 0 0 0 0 0
|
|
7 - 189 60 0 0 0 0 0 0
|
|
35 - 188 140 0 0 0 0 0 0
|
|
Node Count: 5
|
|
|
|
==== MS/TP Usage and Timing Maximums ====
|
|
MAC MaxMstr Retries Npoll Self Treply Tusage Trpfm Tder Tpostpd
|
|
0 1 0 52 0 11 24 0 0 0
|
|
2 0 0 0 0 23 0 0 0 0
|
|
3 6 0 50 0 5 100 0 0 0
|
|
7 34 0 52 0 5 34 0 0 0
|
|
35 127 0 50 0 6 63 0 0 0
|
|
Node Count: 5
|
|
Invalid Frame Count: 0
|
|
|
|
The BACnet MS/TP capture tool also includes statistics which are
|
|
listed for any MAC addresses found passing a token,
|
|
or any MAC address replying to a DER message.
|
|
The statistics are emitted when Control-C is pressed, or when
|
|
65535 packets are captured and the new file is created.
|
|
The statistics are cleared when the new file is created.
|
|
The statistics can be emitted from a file using the "--scan" option.
|
|
|
|
The MS/TP Frame counts use the following abbreviations:
|
|
|
|
Device = Device ID when an I-Am is seen in a capture (trigger with Who-Is).
|
|
|
|
Tokens = number of Token frames sent from this MAC address.
|
|
|
|
PFM = number of Poll-For-Master frames sent from this MAC address.
|
|
|
|
RPFM = number of Reply-To-Poll-For-Master frames sent from this MAC address.
|
|
|
|
DER = number of Data-Expecting-Reply frames sent from this MAC address.
|
|
|
|
Postpd = number of Reply-Postponed frames sent from this MAC address.
|
|
|
|
DNER = number of Data-Not-Expecting-Reply frames sent from this MAC address.
|
|
|
|
TestReq = number of Test-Request frames sent from this MAC address.
|
|
|
|
TestRsp = number of Test-Response frames sent from this MAC address.
|
|
|
|
The MS/TP Usage and Timing Maximums use the following abbreviations:
|
|
|
|
MaxMstr = highest destination MAC address during PFM
|
|
|
|
Retries = number of second tokens sent to this MAC address.
|
|
|
|
Npoll = number of Tokens between Poll-For-Master
|
|
|
|
Self/TT = number of Tokens sent to self (Addendum 135-2008v) and
|
|
number of tardy tokens sent late.
|
|
|
|
Treply = maximum number of milliseconds it took to reply with
|
|
a token after receiving a token. Treply is required to be less
|
|
than 25ms (but the mstpcap tool may not have that good of
|
|
resolution on Windows).
|
|
|
|
Tusage = the maximum number of milliseconds the
|
|
device waits for a ReplyToPollForMaster or Token retry.
|
|
Tusage is required to be between 20ms and 100ms.
|
|
|
|
Trpfm = maximum number of milliseconds to respond to PFM with RPFM. It is
|
|
required to be less than 25ms.
|
|
|
|
Tder = maximum number of milliseconds that a device takes to
|
|
respond to a DataExpectingReply request. Tder is required to be less
|
|
than 250ms.
|
|
|
|
Tpostpd = maximum number of milliseconds to respond to
|
|
DataExpectingReply request with ReplyPostponed. Tpostpd is
|
|
required to be less than 250ms.
|
|
|
|
==== FTDI chip RS-485 converter 76800 baud tricks ====
|
|
|
|
If you are using FTDI chip in your RS485 converter, you can
|
|
alias an existing baud rate on Windows in the FTDIPORT.INF file
|
|
in order to acheive non-standard 76800 bps:
|
|
HKR,,"ConfigData",1,11,00,3F,3F,27,C0,00,00,27,00,00,00,C4,09,00,00,E2,04,00,00,71,02,00,00,38,41,00,00,9C,80,00,00,4E,C0,00,00,34,00,00,00,1A,00,00,00,0D,00,00,00,06,40,00,00,03,80,00,00,00,00,00,00,D0,80,00,00
|
|
|
|
replace the 10,27,00,00 => divisor = 10000, rate = 300 bps alias
|
|
|
|
hex values actual
|
|
----------- ---------
|
|
27,C0,00,00 - 76923 bps => divisor=39.125
|
|
27,00,00,00 - 76677 bps => divisor=39.000
|
|
|
|
Windows XP (from koby3101)
|
|
1) Plug in and locate your USB/RSS85 in Device Manager under ports. Right click
|
|
on it and select Properties. Click Details tab and from the drop down select
|
|
Device Instance Id.
|
|
|
|
2) Click Start, Run and then type regedit.
|
|
Follow this path in the registry
|
|
HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Enum\FTDIBUS
|
|
|
|
Locate the folder that has the same name as what you found earlier Device Instance
|
|
Id in step 1. Click on 0000 folder and then Device Parameters. On the right
|
|
side you will see ConfigData. Right click and select Modify Binary Data.
|
|
Locate the 10 27 which in my case were in 5th and 6th position and replace with
|
|
27 C0.
|
|
|
|
This will make the RS485 go to 76800 baud (76923 baud) baud when you ask it
|
|
to be 300 baud.
|
|
|
|
So to capture at 76800 baud type:
|
|
|
|
From the command line:
|
|
> mstpcap.exe COM2 300
|
|
|
|
From Visual Studio in debug mode:
|
|
Setting project properties -> Debugging -> Command line arguments to COM4
|
|
|
|
Some USB to RS485 converters:
|
|
|
|
Waveshare USB to RS485 converter
|
|
https://www.waveshare.com/product/usb-to-rs485-b.htm
|
|
|
|
B&B Electronics USB to RS485 converter USOPTL4 (isolated)
|
|
https://www.advantech.com/
|
|
|
|
Linux (used with Debian Lenny and Fedora 15)
|
|
http://www.connecttech.com/KnowledgeDatabase/kdb309.htm
|
|
As root:
|
|
Change USB so I can use it later as normal user:
|
|
# chmod 777 /dev/ttyUSB0
|
|
Print current info about the device:
|
|
# setserial /dev/ttyUSB0 -a
|
|
/dev/ttyUSB0, Line 0, UART: unknown, Port: 0x0000, IRQ: 0
|
|
Baud_base: 24000000, close_delay: 0, divisor: 0
|
|
closing_wait: infinte
|
|
Flags: spd_normal low_latency
|
|
|
|
Make custom speed:
|
|
# setserial /dev/ttyUSB0 spd_cust
|
|
24000000/312 gives 76923 baudrate:
|
|
# setserial /dev/ttyUSB0 divisor 312
|
|
Print to make sure changes got applied:
|
|
# setserial /dev/ttyUSB0 -a
|
|
/dev/ttyUSB0, Line 0, UART: unknown, Port: 0x0000, IRQ: 0
|
|
Baud_base: 24000000, close_delay: 0, divisor: 312
|
|
closing_wait: infinte
|
|
Flags: spd_cust low_latency
|
|
|
|
Now as normal user running the mstpcap which uses the default 38400 baud it
|
|
will actually capture at 76800 baud. (76923)
|
|
|
|
Just navigate (cd bin) to bin folder in the project and type:
|
|
|
|
$ ./mstpcap
|
|
|
|
==== Named Pipe direct to Wireshark ====
|
|
|
|
Use the named pipe option to send the capture output directly to Wireshark.
|
|
On Windows, use \\.\pipe\wireshark as the name, and set that name as the
|
|
interface name in Wireshark. On Linux, the named pipe name can be just about
|
|
any file name, such as /tmp/wireshark. See:
|
|
http://wiki.wireshark.org/CaptureSetup/Pipes
|
|
|
|
==== EXTCAP direct from Wireshark ====
|
|
|
|
To use extcap, run Wireshark and go to the About-dialog.
|
|
Find a tab located there named "Folders".
|
|
Locate the extcap search path.
|
|
Copy the mstpcap.exe to that folder, which may not exist.
|
|
Restart Wireshark, and look for "BACnet MS/TP on COMx" interfaces.
|
|
Configure the interface to change baud rate.
|
|
Capture directly from the interface.
|
|
|
|
==== Developer Info about Wireshark ExtCap ====
|
|
|
|
BACnet MS/TP uses a DLT (data link type) requested from and
|
|
approved by libPCAP development team, which is 165. Wireshark
|
|
includes a dissector that decodes the MS/TP packets when they
|
|
use the DLT for MS/TP. Other DLTs exist for other types, and
|
|
there are also DLTs set aside as USER DLTs.
|
|
|
|
See the following URLs for information about ExtCap:
|
|
https://github.com/wireshark/wireshark/blob/master/doc/README.extcap
|
|
https://github.com/wireshark/wireshark/blob/master/doc/extcap_example.py
|
|
https://wiki.wireshark.org/Development/Extcap
|