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how can i filter on a serial port ?


I have an encoder that I attached to it on a serial port an analogue camera and a ptz motor. The camera is controlled via a keyboard specific to this task. In addition, the cable used between the ptz motor and the encoder is coaxial and uses a converter from coax to serial.

I’m having pb with the PTZ when I move the joystick on the keboard to control the PTZ, the camera starts spinning.

I want to take traces when I move the PTZ between this camera and the encoder to try to analyse them. However, I want to filter this trace on IP address of the encoder and that specific serial port that the camera is attached to it . The reason is that I have many other cameras attached to this encoder as well but on different port. How can I do a trace with a filter on a specific serial port through wireshark and how to know the port number? what is the syntax ? should i use the UDP port ? If yes, is this UDP port is different than the others used by other cameras ?

asked 25 Sep '12, 11:34

souss's gravatar image

accept rate: 0%

From what I understand you basically need information about how the camera communicates via IP (for example, if each camera has its own UDP port) - that is something nobody here will know, especially not without you telling us what camera system it is. And even then I doubt we can help you; this is clearly something you need to take to the vendor of the camera equipment I'm afraid.

(25 Sep '12, 15:00) Jasper ♦♦

thanks Jasper for your reply,

In fact yes I do know the UDP port of each camera that is different and yes it is something known by the vendor(he provides it). However I just paid attention that I made a mistake by naming the serial port and asking about it. The reason is : the communication will always be on one serial port as we are treating one IP address. However I might use the UDP port to see this kind of commnication if i need to see a video stream communication .. However if i wanted to see a TCP connection communication I would choose just the IP address of the encoder as it is the only unit that will communicate through the serial link.

I beleive that I originally wrote the question wrongly, I was asking in fact if we can know on a specific physical port if we can monitor the traces and how to see them on one particular camera. here, I can agree with you that it must be the unique UDP port specified by the vendor. However I was wondering how can I know or trace the TCP communication without UDP (= video) between one camera on a specific physical port and the encoder itself

Please tell me if im mistaken or if I missed any confusing detail

Thanks agian and sorry about that


(25 Sep '12, 22:24) souss

One more thing, when I said in my last answer camera, I meant the PTZ motor also as it is the root of the issue

(25 Sep '12, 22:26) souss