J1939 Requests - multiple instances

mbowdich
Posts: 209
Joined: Tue Oct 05, 2010 10:54 am

J1939 Requests - multiple instances

Post by mbowdich » Wed Aug 17, 2011 1:07 pm

I have found that the PV750 is sending both global and address specific requests for all of my requested PGNs. This is resulting in multiple replies from the same node (address specific and global) for each request, which is clogging up the bus and delaying other important messages when multipacket message requests are involved.

My solution has been to not mark request PGNs in the database, and use FFCAN message to send the requests
ksaenz
Enovation Controls Development
Enovation Controls Development
Posts: 263
Joined: Thu Aug 19, 2010 7:53 am

Re: J1939 Requests - multiple instances

Post by ksaenz » Wed Aug 17, 2011 1:12 pm

If the node responds to global requests you can uncheck the box "Request Specific Address" in the Device Setup. This should stop the address specific requests.

Regards,

ksaenz
mbowdich
Posts: 209
Joined: Tue Oct 05, 2010 10:54 am

Re: J1939 Requests - multiple instances

Post by mbowdich » Wed Aug 17, 2011 3:14 pm

The question still remains; Why do both requests get sent? It should be one or the other depending on the check box.
jtabb
Enovation Controls Development
Enovation Controls Development
Posts: 37
Joined: Mon Apr 04, 2011 8:59 am

Re: J1939 Requests - multiple instances

Post by jtabb » Fri Aug 19, 2011 8:02 am

There is a way to disable globals on the J1939 port manager application using the check box "Send Global ISO Requests". This turns off the global requests of all the devices.

Essentially if you have multiple devices you can toggle on/off Specific Address for each device or toggle on/off Global Addresses for all devices. You cannot turn global addresses off for individual devices. This is by design so if you required different operation it would really be a feature request and not a bug.

I hope this helps.
jtabb
FW Murphy Development Team
jtabb
Enovation Controls Development
Enovation Controls Development
Posts: 37
Joined: Mon Apr 04, 2011 8:59 am

Re: J1939 Requests - multiple instances

Post by jtabb » Fri Aug 19, 2011 10:01 am

You can find the "Send Global ISO Requests" under the Instance Information section of the J1939 Port Manager Application on the Environment Setup tab.

Let me know if this solves your problem.
jtabb
FW Murphy Development Team