https://forge.codesys.com/forge/talk/Runtime/thread/9b3d509bc7/2020-02-27T17:39:42.158000ZRecent posts to Access violation exception related to struct and FB_INIT2020-02-27T17:39:42.158000Z2020-02-27T17:39:42.158000Zbeachcabanahttps://forge.codesys.com/u/beachcabana/https://forge.codesys.com30dd8ade48dfcaa9a4a33ce6c1baf120fce2587e

<div class="markdown_content"><p>Hey, there!</p> <p>I'm getting an access violation exception related to the struct "WHEEL_VELOCITIES". This DUT is used in the definition of a new struct, which is used in a function block. The struct "WHEEL_VELOCITIES" is also used as the return type of a method from that same function block.</p> <p>What I find odd is that if I download the program to the Control Win Soft PLC, everything works well. It is only when I try to download to the beaglebone black (after updating the device) that I get this error. Also, if I remove the struct "WHEEL_VELOCITIES" from my code, Codesys still gives me the same error but regarding a different struct.</p> <p>I have not defined any FB_INIT method for any function block and, from what I understand, DUTs don't have a FB_INIT or any other method associated with them, right? Is codesys interpreting my struct as a function block?</p> <p>The error:<br/> <a class="" href="https://drive.google.com/drive/folders/1y5AFK2EZCUrh1scnktNZJvLMgSWup03P" rel="nofollow">https://drive.google.com/drive/folders/1y5AFK2EZCUrh1scnktNZJvLMgSWup03P</a></p> <p>Thank you for your time,<br/> Paulo</p> <p>UPDATE:<br/> Got it working. I believe it had something to do with having set the attribute "{attribute 'pack_mode' := '0'}" in the struct and not in the sub struct. However that was not enough to correct the issue. I also had to remove the modbus slave I had associated with those variables, download and undo the removal.</p></div>