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J1939 Address Claim / Start Address

Metalfor 4 years ago in IQANdesign updated by Ulrik Zakariasson (Software development) 2 years ago 9
Hello, I'm working with a J1939 project in which I want to use a MD4-7 as an instrument cluster. The Cluster must have the chance to make address claim in J1939 with the 23 address. Is that possible? Regards. Diego.
GOOD, I'M SATISFIED
Satisfaction mark by Metalfor 4 years ago
For the J1939 traffic that you set up in the application to interface with other non-IQAN modules, use the property J1939 source address on the master module.





The other property J1939 start address is on the Diagnostics bus. For Master-Master communication, IQAN uses a J1939 based protocol, with addresses starting in the proprietary source address range. Setting this property to anything other than default is is only relevant to use if you have an IQAN system with more than one master on the Diagnostics bus, and also share this physical bus with other J1939 modules.



For the J1939 source address you set on the master module, there is no automatic address claim. To make an address claim for e.g. address 23, you need to build it with a JFOUT channel.
Hello and thanks for information. So now is the incoming question: Why doesn't have for J1939 devices (eg: engine, transmission) an automatic address claim block for use in these cases? Don't you think it will be usefull? Regards. Diego.
That is an interesting question, it has actually been very few times that we have had requests for an automatic address claim message. I guess one reason is that when designing the J1939 network for the application, all the nodes will be know at design-time and have fixed source addresses. But a built-in address claim message could perhaps further minimize the risk of an address conflict having some unintended effect on the system.

One idea for building this up manually using JFIN and JFOUT would be to add a J1939 module with the same address as the IQAN master, and add a JFIN listening to PGN 60928. If it is received, it could be used to block an IDC that enables all other J1939 modules in the system.
To also send out an address claim, a JFOUT channel broadcasting that PGN could be added to this module too. If one wants to send a J1939 NAME that is following J1939-81, then that could take some time to figure out though.


Hello Gustav. When you suggest to add a module with same address than IQAN master, you mean to add it in System Layout? I will try this, and now I need to know a parameter refered to Parker to build up the Name data. Which Manufacturer Code number does it have Parker?
Regards. Diego.
PS: Would be usefull consider to add a programmed block for Address Claim in IQAN so we no need to make such code, only insert few data.
Yes. It will appear a bit confusing in the system layout, but that would be the way to be able to read if the address claim would come from another module trying to claim the same address. Which should of course not happen.
If the requirement is only to send out the address claim and not check for conflicts, you could just use this application:
Send J1939 NAME.ids3
This is sent on trigger on startup. If the requirement is to respond to a J1939 diagnstic tool, then you may want to change the send method to on-request, or duplicate it to do both.

The Parker ECD manufacturer code is 71, so that is what I put in this example.

To read J1939 NAME, you can use this application:
Read J1939 NAME.ids3

Hello Gustav and thanks for information!. One doubt in the example you sent. The "Identity Nbr" declared for JPOUT = 738100. Is it correct? Regards. Diego.
Yes, in the example, I used the same Identity number (738100) that we use for IQAN master modules when making address claim for the multi-master addresses, I think this should be fine to use also for this purpose.

New property on the J1939 bus for address claim introduced in IQANdesign 5.02. Forces IQAN master modules to claim their J1939 address before starting other J1939 communication.