Hey,

I was wondering if anyone had any experience they could share my way with communicating with j1939 messages that have a dynamic address. So far I have only used static address items however I am now looking to use one whose address is assigned anywhere within the valid range. Can I still use the j1939 devices and make some changes to the address type, or would I be better of going for a solution with scripting the raw can data? If this is the case has anyone got some examples of syntax about how to read the raw data (i believe i have a fair understanding about how to send j1939 messages with scripting).

Any help would be greatly appreciated

Hello ADE,

Seems to me you have a couple of options depending on what devices will be on the network with the display and the device with the unknown source address (within a range of addresses).

If the network will be the display, I am assuming you have a color display since mentioned scripting, and this other device, the easy way is to make the device source address 255 in the configuration. This will also work if you know that this is the only device that will transmit the particular parameters on the network. In these cases, you really don't care what the source address is, you are only interested in the parameters.

My guess is, your network is more complicated and you have multiple devices transmitting the same paramters and the display needs to know where they are coming from. Depending on the number of parameters and range of addresses (5 or 25?) in question, you could have a device in the configuration for each source address with a script that scans for the active parameter to display/process.

Then, there is using the FreeForm CAN receive and scripting everything. There is a forum topic that discusses using the raw data packets here viewtopic.php?f=7&t=1084. There is a very simple example in one of the posts that might be helpful also.

This is how I see your options. Maybe others have some ideas also.