Password operated system for preventing unauthorized or accidental computer memory alteration

Claim 1

In a digital computer used to control the operation of a machine, said computer including, a high-speed operating system memory adapted to contain the computer system operating programs, a high-speed program memory adapted to contain at least one of a plurality of the programs used to operate said machine, input and output means for operating and observing the operation of said computer, a low-speed memory device having replaceable easily stored permanent memory elements, said low-speed memory device being capable of storing substantially more information than said high-speed memories thereby permitting storage of said plurality of programs along with the operating system programs and having a protected portion wherein stored information cannot be altered by said computer, said protected portion containing a password that is unique to each one of said memory elements, and means for transferring information between said high-speed memories and said low-speed memory; an automatic lockout device comprising: means for comparing the password in said high-speed operating system memory and the password in said low-speed memory, and means to prevent alteration of information in said low-speed memory when the passwords in said high-speed operating system memory and said low-speed memory do not match.