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Claim 1

IN A DIGITAL DATA PROCESSOR INCLUDING A MEMORY FOR STORING A PLURALITY OF MULTI-BIT DATA WORDS INCLUDING COMMANDS, OPERANDS AND AT LEAST ONE LIST CONTROL WORD WHICH COMPRISES FIRST, SECOND AND THIRD ADDRESS WORDS WHICH RESPECTIVELY CONTAIN THE CURRENT ADDRESS OF AN OPERAND IN A STORED LIST OF OPERANDS AND A CODE PORTION, THE END ADDRESS OF THE LAST OF SAID OPERANDS AND THE START ADDRESS OF THE FIRST OF SAID OPERANDS, A MEMORY ADDRESS REGISTER CONNECTED WITH SAID MEMORY FOR ADDRESSING DATA STORED THEREIN, BUFFER REGISTER MEANS CONNECTED WITH SAID MEMORY FOR PROVIDING BUFFER STORAGE OF DATA READ FROM SAID MEMORY AND FOR RETURNING SAID DATA READ FROM SAID MEMORY TO APPROPRIATE LOCATIONS IN SAID MEMORY, AN ADDRESS MODIFICATION REGISTER CONNECTED WITH SAID MEMORY FOR RECEIVING ONE OF SAID ADDRESS WORDS THEREFROM, SAID ADDRESS MODIFICATION REGISTER BEING CONNECTED TO SAID MEMORY AND TO SAID ADDRESS REGISTER FOR SUPPLYING SAID ONE OF SAID ADDRESS WORDS IN AN UNALTERED OR ALTERED STATE TO SAID MEMORY AND TO SAID ADDRESS REGISTER MEANS, ARITHMETIC AND COMPARISON MEANS CONNECTED WITH SAID BUFFER REGISTER MEANS AND WITH SAID ADDRESS MODIFICATION REGISTER FOR RECEIVING DATA FROM SAID ADDRESS MODIFICATION REGISTER OR SAID BUFFER REGISTER, FOR COMPARING THE DATA RECEIVED FROM THESE TWO REGISTERS AND FOR SUPPLYING THE DATA FROM EITHER OF THESE REGISTERS TO THE ADDRESS MODIFICATION REGISTER INCREMENTED OR DECREMENTED BY ONE, A PROGRAM ADDRESS REGISTER MEANS CONNECTED WITH SAID MEMORY ADDRESS REGISTER AND ADAPTED TO RECEIVE THE ADDRESS OF A COMMAND STORED IN SAID MEMORY AND TO SUPPLY SAID ADDRESS OF A COMMAND TO SAID MEMORY ADDRESS REGISTER TO ADDRESS TO SAID COMMAND, AN ARITHMETIC MEANS COUPLED WITH SAID PROGRAM ADDRESS REGISTER MEANS FOR INCREMENTING BY ONE THE CONTENTS OF THE PROGRAM ADDRESS REGISTER MEANS AND RETURNING THE RESULTS THERETO UPON THE OCCURRENCE OF A SIGNAL FROM SAID CONTROL MEANS EACH TIME A COMMAND IS FETCHED FROM SAID MEMORY, AND CONTROL MEANS CONNECTED WITH SAID MEMORY, SAID REGISTERS AND SAID ARITHMETIC AND COMPARISON MEANS FOR CONTROLLING THE OPERATION THEREOF, THE IMPROVEMENT COMPRISING SAID DATA STORED IN SAID MEMORY FURTHER INCLUDING A PROGRAM INCLUDING AT LEAST THREE COMMANDS STORED IN ADJACENT MEMORY LOCATIONS, THE INTERMEDIATE OF SAID COMMANDS DIRECTING ADVANCE TO ANOTHER PROGRAM OR TO THE THIRD OF SAID COMMANDS AND THE THIRD OF SAID COMMANDS DIRECTING AN ADVANCE TO THE FIRST OF SAID COMMANDS, PREDETERMINED CODES IN SAID FIRST ADDRESS WORD SERVING TO INDICATE THAT A PLURALITY OF SAID LIST CONTROL WORDS EXISTS AND THAT THE CURRENT ADDRESS OF A FIRST OF SAID LIST CONTROL WORDS INDIRECTLY ADDRESS A SECOND OF SAID LIST CONTROL WORDS, SECOND PREDETERMINED CODES SERVING TO INDICATE THAT THE ADDRESS WORD IN WHICH SAID SECOND CODES APPEAR IS A PART OF A LIST CONTROL WORD, SAID FIRST ADDRESS WORD BEING TRANSFERRED TO SAID ADDRESS MODIFICATION REGISTER, SAID SECOND OR THIRD ADDRESS WORD BEING TRANSFERRED TO SAID BUFER REGISTER, SAID ARITHMETIC AND COMPARISON MEANS INCREMENTING OR DECREMENTING THE CONTENTS OF SAID ADDRESS MODIFICATION REGISTER AND RETURNING THE RESULT THERETO AND COMPARING THE CONTENTS OF SAID BUFFER REGISTER WITH THE CONTENTS OF SAID ADDRESS MODIFICATION REGISTER AND PROVIDING AN OUTPUT SIGNAL WHEN THESE CONTENTS ARE UNEQUAL, STORAGE MEANS COUPLED WITH SAID ADDRESS MODIFICATION REGISTER AND SAID ARITHMETIC AND COMPARISON UNIT FOR RECEIVING FROM SAID ADDRESS MODIFICATION REGISTER THE STATUS OF THE CODE PORTION AND STORING THE STATUS THEREOF, AND STORING SAID OUTPUT SIGNAL FROM SAID ARITHMETIC AND COMPARISON UNIT, SAID STORAGE MEANS PROVIDING A PREDETERMINED OUTPUT SIGNAL WHEN PREDETERMINED CODES ARE STORED THEREIN AND WHEN NO OUTPUT SIGNAL IS RECEIVED FROM SAID ARITHMETIC AND COMPARISON MEANS FOR CONTROLLING SAID CONTROL MEANS TO CAUSE SAID ARITHMETIC MEANS TO AGAIN INCREMENT THE CONTENTS OF SAID PROGRAM ADDRESS REGISTER MEANS A SECOND TIME TO SKIP SAID INTERMEDIATE COMMAND, WHEREBY SAID FIRST COMMAND IS EXECUTED FOLLOWED BY SAID THIRD COMMAND BEING EXECUTED, OR TO CAUSE SAID CONTROL MEANS NOT TO PROVIDE A SIGNAL TO SAID ARITHMETIC MEANS TO INCREMENT SAID PROGRAM ADDRESS REGISTER A SECOND TIME WHEN SAID STORAGE MEANS PROVIDES SAID PREDETERMINED OUTPUT SIGNAL WHEREBY SAID INTERMEDIATE COMMAND IS NOT SKIPPED, AND SAID CONTROL MEANS SERVING TO SENSE PREDETERMINED CODES AND TO SUPPLY APPROPRIATE OUTPUT SIGNALS TO ALLOW OR NOT TO ALLOW THE EXECUTION OF SAID FIRST COMMAND DEPENDING UPON THE STATUS OF SAID PREDETERMINED CODES.