PulseView and CAN decoder demo
Вставка
- Опубліковано 29 вер 2024
- Shows Sigrok PulseView with the can2 CAN protocol decoder being used to decode CAN signals from a bus. Also shows how the low-level view of the protocol can show attacks on the CAN bus that are invisible at the higher frame level.
PulseView can be downloaded from the Sigrok web site: sigrok.org/wik...
The can2 decoder can be downloaded from the CANHack repository: github.com/ken...
Busmaster can be dowloaded (for Windows only) from: rbei-etas.gith...
The PiCAN hat for the Raspberry Pi can be bought from SK Pang: skpang.co.uk/c...
To stay informed about CAN then regularly visit my blog: kentindell.git...
You had a number of different things going on in the video. For the sigrok/pulseview analyzer it seems you used a standard saleae logic analyzer on the CAN bus receive line to capture the bits and a CAN decoder plugin that performed the actual CAN protocol analysis. Is that correct? For my use case I just want to monitor automotive CAN bus traffic.
How do i get the can2 decoder into Pulse view? I have purchased your CANPico and I have got it in the mail today here in Australia. Looks great.
You can set an environment variable, but the simplest is to put it in your home directory on Linux:
~/.local/share/libsigrokdecode/decoders
or on Windows:
%ProgramData%\libsigrokdecode\decoders
You can also use the environment variable SIGROKDECODE_DIR to point to where the decoders are.
What is can rx Line in pulse view and can we connect can tx line to one of the channel
A CAN transceiver has two digital pins: CAN TX is the output of the CAN controller, and CAN RX is input to the CAN controller. Decoding CAN RX is the same as decoding the CAN bus. You can decode CAN TX too: you just add a second decoder to the CAN TX line in the logic analyzer. But the decoder will flag a potential error because the TX line is missing the ACK=0, but otherwise this is fine.
Generally you only bother to decode RX because what is sent on TX gets looped back, but you very often want to connect the TX pin to the logic analyzer at the same time because you can then see whether the device was transmitting or receiving: if it's receiving then it will send recessive bits except for ACK=0, if it's transmitting then TX and RX lines will look the same.