Transmission of J1939 messages

  • Software
  • Transmission of J1939 messages
Phil Gooch

Posted on 08.08.2017 07:02

I have read through the CAN related training but I'm still not clear on how I can achieve what I need.

Attached is an extract from a vehicle body builder guide which, includes a very useful example of how to achieve a particular command (engine start) by sending a message to the truck by J1939. However, I'm not sure how I can take this information and use it in DeweSoft.

I have cut a lot of pages from the original document, leaving those I believe are relevant. The command I would like to achieve is Remote Engine Start Switch as used in their example on the last page.

What I cant work out is how I translate the Engine Start example into something that I can use with DeweSoft - Essentially I would like to click a button in Dewesoft to stat the vehicle engine.

The example gives the full message details, but I assume I dont actually enter it in that form and I should be trying to configure the message in Dewesoft to change the state of the relevant bit?

On a minor point, it would be useful for us irregular users of DeweSoft if the Bit/Byte table could be modified to indicate which are the bits and which are the bytes - Regular users will obviously remember this but a simple heading for each would be great - An example of this is shown in the table at the top of the first page attached.



Attached files:
Primož Gorenšek
Automotive Application Engineer
Posted on 08.08.2017 10:28

Dear Phil,


In Dewesoft it is in some cases better to send standard CAN messages and define them as J1939. The reason why J1939 can not be used for transmit of your message is the arbitration ID which is too long for J1939.

I have attached an XML file of the messages already defined in Dewesoft. You just need to import them and create button channels and assign them to corresponding messages for engine ON and OFF. From what I have read you first need to send engine OFF request and then engine ON.

The user interface is planned to be redesigned and improved shortly and we will also take you suggestion into consideration.


Attached files:
Phil Gooch

Posted on 08.08.2017 16:17

Thanks for your reply.

In order to use other commands from the documentation, such as "Remote engine shutdown request" I assume I need to add them to the XML file using the same structure as you have in your example? This appears to be achievable using Notepad.

I have imported the XML file into DeweSoft in (simulation mode) and both engine start and stop channels/messages appear identical when comparing the Setup window for each (see attached). I can see in the XML file that the messages are actually different, so why do they appear identical in DeweSoft?





Attached files:
Primož Gorenšek
Automotive Application Engineer
Posted on 10.08.2017 10:17

I forgot to mention that you need to upgrade your version of Dewesoft to the latest one. You seem to be using one of the older versions where it was not possible to send raw hex values over CAN. I have attached a screen showing how the setup should look like. I have also forgot to change in one of the massages the type to extended so I have also attached the XML file again.


Best reagrds,

Primoz


Attached files:
Login to reply to this topic. If you don't have account yet, you can signup for free account .