Control apparatus for digital computers

Claim 1

IN A DIGITAL COMPUTER INCLUDING AN INTERNAL STORAGE MEANS FOR STORING A PROGRAM COMPRISING PRESELECTED COMMANDS AND INFORMATION TO BE OPERATED ON AT PREDETERMINED ADDRESSES IN THE STORAGE MEANS, EACH COMMAND SPECIFYING AN OPERATION TO BE EXECUTED AND AN ADDRESS IN THE STORAGE MEANS OF THE INFORMATION TO BE FETCHED UPON WHICH THE OPERATION IS TO BE EXECUTED, THE OPERATIONS TO BE EXECUTED INCLUDING ARITHMETIC OPERATIONS HAVING SUCCESSIVE ADDRESS PORTIONS AND CONDITIONAL TRANSFER OPERATIONS HAVING AN ADDRESS PORTION FOR CHANGING THE SEQUENCE OF THE SUCCESSIVE ADDRESSES OF THE COMMANDS BEING EXECUTED, THE CONDITIONAL TRANSFER COMMANDS BEING ARRANGED IN THE STORED PROGRAM AFTER A COMMAND WHICH IT IS ANTICIPATED WILL PRODUCE AN OVERFLOW IN A PRESELECTED REGISTER, AN ORDER-ADDRESS REGISTER, MEANS FOR SUCCESSIVELY FETCHING THE COMMANDS AT SEQUENTIAL ADDRESSES IN SAID STORAGE MEANS AND STORING THEM IN THE ORDER-ADDRESS REGISTER, MEANS COUPLED TO SAID FETCHING MEANS TO BE RESPONSIVE TO A COMPLETED FETCHING OPERATION FOR EXECUTING THE COMMAND IN THE ORDER-ADDRESS REGISTER AND TO INITIATE THE NEXT FETCHING OPERATION, AT LEAST A SINGLE PRESELECTED STORAGE REGISTER ADAPTED TO INDICATE AN OVERFLOW INDICATIVE OF A PRESELECTED CONDITION WITHIN THE COMPUTER OF AN EXECUTED COMMAND, AN OVERFLOW CONTROL ELEMENT SWITCHABLE BETWEEN A NON-OVERFLOW AND AN OVERFLOW CONDITION AND NORMALLY ARRANGED IN THE FIRST CONDITION, MEANS FOR SENSING SAID STORAGE REGISTER INDICATING AN OVERFLOW AND COUPLED TO SAID CONTROL ELEMENT TO PLACE SAID CONTROL ELEMENT IN THE OVERFLOW CONDITION UPON SENSING AN OVERFLOW, AND CONTROL MEANS COINCIDENTALLY RESPONSIVE TO THE TWO CONDITIONS OF SAID CONTROL ELEMENT AND TO A SIGNAL FROM SAID EXECUTING MEANS REPRESENTATIVE OF A FETCHED CONDITIONAL TRANSFER COMMAND AND OPERATIVE TO CAUSE THE COMPUTER TO IGNORE THE CONDITIONAL TRANSFER COMMAND OR TO NEXT FETCH THE COMMAND AT THE ADDRESS ACCOMPANYING THE CONDITIONAL TRANSFER COMMAND.