====== Controller runtime update ======

To execute the compiled program in a PLC, a runtime (RT) is necessary. The runtime must be up-to-date with the version of the editor (Mervis IDE). A new PLC which comes from the production may not be loaded with the most recent version of RT, and thus it is necessary to update the runtime before a project is uploaded to the PLC. A red triangle at the version number in the list of found PLCs indicates an obsolete version of the runtime.

  * **Yellow triangle**: it was not possible to read the runtime version (most probably an active UDP firewall or another network issue)
  * **Red triangle**: obsolete runtime version, please update the runtime to continue
  * **Grey triangle**: obsolete runtime version, however not critical. The update is recommended, although not necessary.


{{:en:mervis-ide:35-help:attach_plc_04_attach_controller_dialog.png}}

RT update is possible if a PLC is reachable over TCP and [[:en:mervis-ide:35-help:015-plc:005-attach_plc|its platform is correctly attached]].

Update the runtime by right-click on the controller, select "PLC Operation" and „Upload RT“. The controller is restarted automatically after the new version of RT is uploaded.

{{:en:mervis-ide:35-help:upload_rt.png}}