Patents by Inventor Walter V. Casto

Walter V. Casto has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Program protection module for programmable controller
    Patent number: 4118789
    Abstract: A program protection module for a programmable controller checks the critical, or protected, portion of the control program each time the controller is switched to the run mode. This is accomplished by reading each control program instruction out of the controller memory and comparing it with a corresponding control instruction stored in a nonaccessible read-only memory. If all the compared control instructions are identical, the module sets a status bit in the programmable controller which enables the protected portion of the control program to be executed. If identity is not found, an alarm is generated and the protected program is not executed.
    Type: Grant
    Filed: June 6, 1977
    Date of Patent: October 3, 1978
    Assignee: Allen-Bradley Company
    Inventors: Walter V. Casto, Lawrence W. DeLong, Theodore J. Markley, Odo J. Struger