I am trying to understand a manual of a smart light strip, because I want to control my light strip from my PC. And at page 5 cap. '3.1 Search request and response' I don't understand where I should type that searching message. Thanks.
Manual : https://www.yeelight.com/download/Yeelight_Inter-Operation_Spec.pdf
Just as described in the manual, you should write the content of the search message into a UDP datagram and send that to the multicast address 239.255.255.250:1982
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I want to make a node which can overhear neighbor's sending packets and print the information of the packet in Mote output cooja. And I also hope the node doesn't send or forward any packets. What can I do?
Sounds like you want a sniffer. Check out examples/sensniff for an example on how to implement that.
To go into more detail, you most likely need to disable the network layers above radio (use "nullnet") with MAKE_NET=MAKE_NET_NULLNET and implement a custom MAC layer, like the SenSniff example does.
I need to capture https traffic. In particular the client hello messages. But I need to analyse their content. I learned about wireshark. How can I to extract the data from the packet content? i.e. the client hellp content? The tool displays the packets. If I click on them, I see more information but how to aggregate them. i.e. I need the field length (as shown in the picture) for all client hello messages?
Are there any tools to do so? Or can Wireshark do this function?
EDIT: In the picture, this is a client hello message. I need some data like the length. How to extract this and aggregate it for large traffic?
Image for illustration
You can do this with wireshark with a filter of "ssl.handshake.type == 1". This will give you all Client Hello packets. From there you can manually inspect the client hello message or you can even make any field in the client hello message a column in Wireshark. To do this, drill-down into one of the packets to the field you want to see. Right-click that field and select "Apply as Column".
If you want to do this programmatically, you could also write a program that uses libpcap to capture packets. This is more work though since you would have to manually dissect the packets yourself.
Currently, i'm working with HLK-RM-04 wifi to UART module. I'm using this in server mode. I've connected this module(tx/rx) to my PIC16F887. Connections are fine and I can able to transmit and receive data.
All i'm doing here is giving a html request from a browser/web client, and i'm expecting my data(responded from my MCU) to be displayed in browser. But i'm not getting it properly. Sometimes it works in right way, but most of the time if displays some junk value.
To analyze from MCU side, i tapped my MCUs Tx pin and connected to PC COM port. Yes, it seems it works perfect. I can able to see my data in hyper terminal, what i'm transmitting from MCU.
So to analyze from PC side, I used a free web-sniffer. There I can see data received was junk at sometimes. (Pls refer images) I couldn't able to guess whats wrong ?
Data sent to wifi module from MCU was right, but data sent from wifi module as wifi frames are bad ?
Is that any way to analyze further ?
Expected response - 1 out of 5 request wins:
bad response 2:
I don't remember when I was using HyperTerminal for the last time and I am not sure will it show whitespace characters (if I remember there is such settings).
One of the things that I would try is to install serial port sniffer or some advanced terminal (like Realterm) and verify that there is no some junk in form of white space characters that are hidden in HyperTerminal.
I am using wireshark to look at ddp/rdma packets, which usually works fine.
Sometimes wireshark can't recognize that the next protocol after tcp is ddp/rdma (although I know it is), so I tried using "decode as" but there is no option for ddp/rdma in there.
Is there a way to force wireshark to parse the packet as ddp/rdma?
Thanks!
Is there a way to force wireshark to parse the packet as ddp/rdma?
The dissector for iWARP DDP/RDMA, if that's what you're referring to, is a "heuristic" dissector, which means that 1) it looks at otherwise-undissected TCP packets and tries to guess whether they're packets for it and 2) it doesn't have a "force this" option.
You should submit a bug to the Wireshark Bugzilla saying that Wireshark isn't recognizing the traffic as DDP/RDMA, and attach a sample capture.
I am a complete CAN bus newbie. I'm hoping someone with CAN experience can point me in the right direction. I was given a Vector VN1610 USB to CAN adapter and a Continental ARS-308 radar sensor. The goal is to read some velocity and distance information from the sensor. Right now I am just trying to see any data but all I get are messages with an id of 0 or 0x80000000. The data payloads all report as 8 bytes of 0.
What Works
I have been able to use the sample .NET code provided and set up the VN1610. The ARS-308 has a single CAN channel so in the Vector Hardware Config for my application I just map "CAN 1" to VN16101 Channel 1. (I leave CAN 2 unassigned) I then assume I use that one channel for both transmit and receive. The code reports that the channel sets up an activates and no errors are reported.
I then have a thread looking for incoming messages. If I don't debug out the two IDs mentioned above I can actually process all of them and then I get XL_ERR_QUEUE_IS_EMPTY messages. So it looks like its all working, I'm just not getting any real data.
What Doesn't
I would think a slew of data messages in the 0x200 - 0x702 range would be coming in for the Continental ARS device. Now I'm more used to ethernet type protocols where I would send a command and then read a response. None of my docs talk about how CAN works so I am ASSUMING that in CAN the device just sends data. I certainly can't find any commands that tell the device to send me the particular msg ID I'm interested in.
Am I missing some basic CAN configuration step that informs the device it should start sending data? Any suggestions at all would be appreciated.
If it matters I'm writing in VS2013, .NET on a Win 7 64 Ultimate machine.
The answer is No. It turns out that CAN devices will indeed just start streaming out messages when you turn them on (well at least this one does). The messages with ids of 0x0 and 0x8000000 are bogus. Even with the radar sensor turned off I continued to see those messages.
It turns out I had a hardware problem. The CAN bus requires a 120 Ohm resistor which was installed. The problem was when the shell was put back on the cable the resistor got cracked. Once we repaired this, everything started working as expected.