I've bought a used Masturn lathe with a Grundig Manual Plus control (earlier Phillips later Heidenhain Manual Plus), but due to battery failure the contents on the flash disk has been corrupted. When I try to start the machine, I only get "Operating system not found".
Is there anyone who knows how to restore the dos operating system on this control? From what I've read in the manual, I think there should exist a restore disk, but no such disk followed the lathe.