creating a CAN segment in middle of LIN bus

RS-232 to CAN/LIN Interface
Post Reply
R1MARC
Posts: 15
Joined: Tue 27. Nov 2018, 12:50

creating a CAN segment in middle of LIN bus

Post by R1MARC » Wed 28. Nov 2018, 15:39

Hello,

I'm working on a project to create a CAN segment on a LIN BUS (get a longer distance and have a non electric medium).
After a quick serach on Internet, I found your PCAN-LIN gateways and assume they are able to do the job.
Now I've the 2 parts and work on a demonstration.

It goes quite good for one direction: The LIN slave updates its data, collected by a gateway#2 (in 5.2 example configuration), transfered on CAN Bus, collected by gateway#1 (in 5.5 example configuration) and then delivered on LIN bus on LIN master request.
For the opposite direction, I've no reaction on LIN slave.
Data set by LIN master are collected by gateway#1, sent on CAN bus (with Offset of this gateway CANID=CANIDOffset+LIN ID) but don't goes to LIN Slave.
I think the issue is that you add +0x40 in this direction, creating a new LIN ID not defined.

Is there a misunderstanding in my configuration?
Is it possible with your modules to do such a bidirectionnal gateway system?
If so, let me know what I should do to get right operations.

Attached my configurations files: gateway#1 is Slave, from LIN bus point of view, and gateway#2 is Master, from LIN bus point of view.
Attachments
config_Slave_Tester.pclin
(43.17 KiB) Downloaded 291 times
config_Master_Siège.pclin
(43.31 KiB) Downloaded 261 times

M.Maidhof
Support
Support
Posts: 1307
Joined: Wed 22. Sep 2010, 14:00

Re: creating a CAN segment in middle of LIN bus

Post by M.Maidhof » Wed 28. Nov 2018, 16:27

Hi,

unfortunately this will not work with PCAN-LIN, due to the 0x40 message offset for CAN publisher data. Why not using the PLIN-LWL module for such an application?

https://www.peak-system.com/PLIN-LWL.408.0.html?&L=1

best regards

Michael

R1MARC
Posts: 15
Joined: Tue 27. Nov 2018, 12:50

Re: creating a CAN segment in middle of LIN bus

Post by R1MARC » Wed 28. Nov 2018, 16:36

Because for internal reason, we already have our "non electrical transmission kit" and it communicates at the moment only with CAN protocol.
All documentation I read before we purchased the parts was about a "CAN / LIN gateway", I've not found any restrictions on its usage.
As far I understand, your gateways can work in both directions but can't be combined to make a "null modem transmission between LIN buses". Is it correct? What's the reason for that?
Is there an opportunity to have a version without such offset (or one offset "CAN to LIN" and one offset "LIN to CAN")?

Our configuration is
Tester <= LIN => Gateway#1 <= CAN (wired / non electrical / wired) => Gateway#2 <= LIN => Equipment
As a result we need full bidirectionnal gateways to be combined together around CAN.

We now have to look for an other solution and pay again for parts :-(

M.Maidhof
Support
Support
Posts: 1307
Joined: Wed 22. Sep 2010, 14:00

Re: creating a CAN segment in middle of LIN bus

Post by M.Maidhof » Fri 30. Nov 2018, 12:09

Hi,

when the PCAN-LIN will use the same CAN IDs for changing the publisher frames and also transmitting the received LIN frame, it will cause arbitration crashes on the CAN due to the fact that it is not allowed to transmit the same CAN ID from different CAN nodes at the same time!

For your application, you have to implement a CAN router on the CAN (see PCAN-Router), which will control the different PCAN-LINs and use two separate CAN segments for the communication to the PCAN-LIN modules. The PCAN-Router can send the needed frames with the offset again on the different CAN systens. I know about customers, who had implement such an application with two PCAN-LINs and a PCAN-Router. Their aim was also to manipulate the LIN data between the two LIN systems, which could be easily realized in the PCAN-Router software.

And yes, the PCAN-LIN is a very usefull LIN-CAN gateway tool, but you must keep the protocol specific limits.
If you have contacted our support team upfront, and have asked us about your intention, we would have been able to send you all necessary information.

regards

Michael

R1MARC
Posts: 15
Joined: Tue 27. Nov 2018, 12:50

Re: creating a CAN segment in middle of LIN bus

Post by R1MARC » Tue 4. Dec 2018, 08:38

OK, I'll no longer trust documentation of products and always have to contact technical support team when I'll look for a product. Thanks for your support.
Topic can be closed

M.Maidhof
Support
Support
Posts: 1307
Joined: Wed 22. Sep 2010, 14:00

Re: creating a CAN segment in middle of LIN bus

Post by M.Maidhof » Tue 4. Dec 2018, 13:54

Yes, good idea!

regards

Michael

Post Reply