We have a tomography device which measures 66 capacitance values for each scan and can send max 100 scans in one second.
It has a special software but I want to get the data into LabVIEW.
I know the IP address, the port number that the data is streamed and the protocol (TCP).
I created a TCP receiver circuit and tried to get the data from the IP address and the port.
When I run the vi, in netstat (DOS) I see that the communication is established.
Can anybody suggest me a method for receiving the data? What else should I know?
That code seems incomplete. How does the instrument "stream" the data? HOw does it know when to start streaming?
At the moment, you are opening a connection and then listen for data. Don't you need to send a command to initiate the streaming? Are you sure it is not UDP?
Can you point to a web site that describes the communication you are trying to establish.
Do you have an existing non-LabVIEW program that can successuflly receive data? You could use it while minitoring the network traffic via wireshark to get a better picture on what is needed.
Yes, "streaming " is not a correct definition. There should be a start command, which probably sent from the software of the device while setting up the communication.
In datasheet it says that the protocol is TCP/IP. Unfortunatley there is no more information.
Yes, we have the software software of the device, which can receive data from the device.
Tomorrow I will try wireshark to get more informatin:)
Today I run wireshark while acquiring data from the tomography device.
The devices IP address is: 192.168.0.27
Any advices for the next step?
OK, it's TCP. Good to know.
At the moment we are looking at the middle of a communication. You need to start capturing before you start the communications program. Add a filter to only look at communications involving 192.168.0.27.
We need to see the threeway handshake establishing the connection (SYN,SYN-ACK, ACK) and the initial communication packets where potentially interesting commands are exchanged.
Currently, all we see are sets of two data packets (one full size, the other with a 256 payload) and ACKs from the computer.
It might also be interesting to see what happens if the communication is stopped at the end.
Hi again Altenbach,
I made a short data acquisition (including start and stop) and captured whole data traffic.
While starting the software
1. A box pops up for entering the IP address
2. Then it asks to fill the capacitance measuring tube with low permittivity material >> next>>( after clicking next, the machine gives a "beep" sound sound)
3. Then it asks to fill the capacitance measuring tube with high permittivity material >> next>>( after clicking next, the machine gives a "beep" sound sound same as step 2)
4. A pop up box comes up written "DONE" After clicking the button (again "beep"), live tomography image comes to the screen.
Sorry for writing too much. I just wanted to write about the initializations.
I have added a .txt file and .pcap file in case you want to take a look.
This won't be that easy without documentation. Many packet payload seems to contain some binary header that presumably indicates to the software what kind of packet we have (commands, settings, data, etc.) This header always starts with FFFF followed by some numbers. Hard to tell.
The good new seems to be that the computer never sends out anything and just passively receives the data. none of the packets originating from the computer ever contain any payload. They just initiate and maintain the connection.
It should be possible to receive the raw data, but parsing it in a meaningful way might need significant work without proper documentation.
Ok, now I know the status at least:)
Thanks a lot Albentach.
I will try hard to get the documentation from the supplier.