SAE j1939

[georgp]

I am trying to send can bus messages to a device that can log J1939. The can analyzer I use and the settings on Flowcode firstly differ I set it to 125 kHz in flowcode and the analyzer too 100 kHz to se the codes coming through. This now with atmel and microchip Can. I need some test code on J1939 if anybody used flowcode successfully with J1939.
Thanks

[Jordy101091]

Hi georgp,

Im not that experienced with CAN BUS let alone SAE J1939.
But to learn something to, it will be my pleasure to help you as for as I can.

this is from another (related) post on the forum

Tell us more what you want to do with the SAE J1939 standard.
I know that the SAE J1939 protocol is used in the automotive industry, for communication diagnostics.
If Im correct this this standard is mostly used in the USA.

Also does Fleet Management Systems Interface (FMS) say anything to you.

I don't know if the Standard SAE J1939/71 is s pdf document but I think that this document contains all the information you need to
to get started with receiving messages and look what they are.

Did you start on you Flowcode, or do you need to create this from scratch.

Rg, Jordy

So can you explain to me/us what you are planning to create using the SAE 1939 standard.
Also it will be good to know if you know how the can messages are built up. Did you research this on the web.

Anyway,
If I understand correctly, you are sending can messages with flowcode to a device that logs J1939 standard messages. I expect that you are not receiving anything because from your story I can tell that you do not have clue how the J1939 messages are built up. second thing I noticed is, why do you have to different bus frequency's, these should be the same, at least thats what I think.

Rg, Jordy

[georgp]

Yes I have a Teltonika uni that accepts can information on J1939 I want to add some information but keep on sending 0 . Timing seems to be also a problem. The way Flowcode handles the ID etc I find a bit difficult to understand how to map to J1939

[Jordy101091]

Ok georgp,

First one thing I want to say is, I think you did not search hard enough to get the information you are after.
If you took the extra bit of effort, and you searched in google for "J1939 Message Format" there is a lot of information available to, at least get you started.

You may see this as criticism, but really i try to make a point here. Because you did not share your flowcode program with us, so we can have look at you work and possibly make some changes to it or give you hints. you mentioned using flowcode to communicate with analyzer, why not share you program with us.

The way I see it, the users of this forum (including my self) need to do all the work in succeeding with there project, we "the forum" are only there to assist you on the way to succes.
Don't take this to hard, Im not going to hunt you down.

Anyway,

I found this document on the world wide web, its from microchip. On page 3 it describe in quite bit of detail how the J1939 message is built up.
I hope you can do something with this.

Regards Jordy

http://ww1.microchip.com/downloads/en/A ... 00930a.pdf