https://forge.codesys.com/forge/talk/CODESYS-V2/thread/dc1b0be745/2020-02-27T23:12:20.627000ZRecent posts to Low Level Can Communication Driver from scratch2020-02-27T23:12:20.627000Z2020-02-27T23:12:20.627000Zvincidohttps://forge.codesys.com/u/vincido/https://forge.codesys.com6f253fc777fe0c28dd917ef40cce756961f0f8e2

<div class="markdown_content"><p>After an hard fight I discovered that the problem was due to a bug in the communication stack library. The CAN chip manufacturer issued an updated interface library that the PLC manufacturer linked in the firmware and now everything works like a charm!<br/> At the end the problem was in the device and not in the CodeSys development system.<br/> Regards D</p> <p><img alt="IMG: sshot.png" rel="nofollow" src="https://forum.codesys.com//download/file.php?id=2468"/></p></div>

2020-02-27T23:12:14.810000Z2020-02-27T23:12:14.810000Zvincidohttps://forge.codesys.com/u/vincido/https://forge.codesys.com28ac1f3676d34ae6131e0b472f1dc6ea8181c0dd

<div class="markdown_content"><p>Hello,<br/> I'm involved in the development of a CodeSys application where the external devices are interfaced by means of a Can bus communication; I'm in charge of the application layer development for a protocol very similar to the SAE J1939 one but with several customized messages. Our objective for this project is to rely on the CodeSys "3S_CanDrv.lib" library for the low level communication primitive (Initialization, Bus handshake, Read/Write message, ...) while we have to write the management code for the data contained in the messages by directly accessing the Rx/Tx buffers. I need to develop the code from scratch without chance to use third party libraries.<br/> I successfully set a CAN communication channel between the PLC where CodeSys runs (master) and the device to be controlled (slave) and I'm able to read good data in the 3S_CanDrv.lib pCanRxBuffer Global Variable.<br/> Anyway I'm stuck on a little problem. It seems that the 3S_CanDrv.lib is set to manage 11bits CanID while I need to manage 29bits CanID.<br/> Just to better explain, if I send from the client the CanID 0x18FF4400 what I get in the pMessageRx.dwID is 0x0000063F.<br/> Can anyone tell me how to set the 3S_CanDrv to handle 29bits CanID (Can 2.0B)?</p> <p>The can driver documentation is really poor and I didn't find any solution after an hard search over internet.</p> <p>Thank you, Domenico</p> <p><img alt="IMG: CanIDTest.png" rel="nofollow" src="https://forum.codesys.com//download/file.php?id=2350"/></p></div>