https://forge.codesys.com/forge/talk/Runtime/thread/2f7caec66a/2021-05-18T07:44:29.194000ZRecent posts to Raspberry not retain var2021-05-18T07:44:29.194000Z2021-05-18T07:44:29.194000Zaliazzzhttps://forge.codesys.com/u/aliazzz/https://forge.codesys.comc48753b77309f51a55c120e6a3d9dd9f3069efa5

<div class="markdown_content"><p>Without extra soft or hardware the Pi will never save retain variables out of its own.</p> <p>Either a non volatile ram hardware (nvram) solution is needed. I have built a special library for an RTC chip which has also NVRAM support or you could use to have a working UPS (uninterruptable power supply) connected to the pi. Then the runtime store the retain data to a file on exit of Linux (a graceful shutdown is needed) and restore them on restart. </p> <p>So without additional effort it won't work as the Pi has never been designed to support this via hardware.</p></div>

2021-05-18T07:07:34.871000Z2021-05-18T07:07:34.871000Zmasterofplchttps://forge.codesys.com/u/masterofplc/https://forge.codesys.comf2cdf41e63bb2b18d96cc0ab485b4850884241d5

<div class="markdown_content"><p>Goodmorning.<br/> I have a project on a raspberry pi 3. When reboot or turn of the raspberry, values of retain var are lost.<br/> the codesys version is 3.5 sp16 patch 4.<br/> The runtime raspberry is 4.0.1.0<br/> I cheked in the application folder on raspberry,the .ret file dont exist.<br/> if I issue the save command on the shell the file is created.</p> <p>thank you</p></div>