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LabVIEW
Re: XNET CAN ID
Hi,
i need one help in the monitoring CAN bus data and i am facing problem identifier is changing continuously logging with different numbers in the monitor, can you give solution for solving the issue.
For easy understanding i am giving screen shot.
@ssrao wrote:
i am facing problem identifier is changing continuously logging with different numbers in the monitor, can you give solution for solving the issue.
The solution to this issue is to have the other devices on your CAN bus use the same identifier all the time instead of changing the ArbID…
Are you familiar with CAN bus? How many devices did you connect with this specific CAN bus?
It is a poor CAN bus design, to use the same ID for multiple devices if that is what you are asking about. I made an analogy years ago about a ringing phone that applies here:
Lets pretend I have phone at home, but I'm really cheap. And instead of answering the phone and being charged with the minutes, I tell a friend of mine to call me, and let it ring once then hang up. I tell this friend that if he does this I know he is wants me to come over. If he lets the phone ring twice and hangs up then that means he is coming over. If I get a second friend and we want to have the same arrangement then I hope it is clear to you that we can't just let the phone ring once or twice, because those signals have already been used. If I tell the second friend to let the phone ring once then I won't have a way of knowing which friend is calling, or what they want. Maybe the second friend calling and ringing once means he his coming over, or does it mean he wants me to come over? Or it could mean something all together.
There isn't anything stopping my phone from ringing any number of times, from any caller (just like CAN anyone can use any ID) but be aware that by doing that you lose the ability to know who called and for what purpose.
More on CAN basics can be found in Part 2 of my CAN blog which does cover the typical uses of the CAN ID.
