Roll call generator

Claim 1

A ROLL CALL GENERATOR SERVING A PLURALITY OF DIFFERENT LINES OF EACH OF WHICH HAS A PREDETERMINED NUMBER OF STA TIONS ASSOCIATED THEREWITH TO BE ROLL CALLED, EACH SEPARATE STATION OF ANY ONE LINE BEING IDENTIFIED BY A DIFFERENT ADDRESS; SAID GENERATOR COMPRISING A STORAGE DEVICE INCLUDING A PLURALITY OF GROUPS OF CONSECUTIVE SLOTS, EACH OF SAID LINES HAVING AT LEAST ONE OF SAID GROUPS CORRESPONDING THERETO AND EACH OF SAID GROUPS INCLUDING AT LEAST AS MANY CONSECUTIYE SLOTS THEREIN AS THE PREDETERMINED NUMBER OF STATIONS ASSOCIATED WITH THE PARTICILAR LINE WITH THAT GROUP CORRESPONDS, INFORMATION COMPRISING THE ADDRESS OF EACH STATION OF EACH PARTICULAR LINE BEING STORED IN A SEPARATE SLOT OF SOLELY EACH OF SAID GROUPS CORRESPONDING WITH THAT PARTICULAR LINE, EACH OF SAIDSLOTS HAVING CONTROL INFORMATION STORED THEREIN, AND READOUT MEANS FOR CYCLICALLY SCANNING EACH OF SAID SLOTS IN SEQUENCE FOR READING OUT THE INFORMATION STORED IN EACH SLOT IN RESPONSE TO THAT SLOT BEING SCANNED, SAID CONTROL INFORMATION UPON BEING REA OUT PROVIDIND FIRST CONTROL SIGNALS FROM WHICH THE RELATIVE ORDINAL POSITION OF A SLOT BEING SCANNED WITHIN A GROUP AND THE RELATIVE ORDINAL POSITION OF THE GROUP INCLUDING THE SLOT BEING SCANNED WITHIN A CYCLE MAY BE DERIVED, AND FURTHER PROVIDING A SPECIAL CONTROL SIGNAL FROM A SINGLE SLOT OF EACH GROUP WHEN THAT SINGLE SLOT IS BEING SCANNED; FIRST MEANS PRODUCING SECOND CONTROL SIGNALS MANIFESTING THE RELATIVE ORDINAL POSITION WITHIN A CYCLE OF A GIVEN GROUP WHICH CORRESPONDS TO THE LINE THEN TO BE ROLL CALLED; SECOND MEANS COUPLED TO SAID FIRST MEANS AND SAID READOUT MEANS AND RESPONSIVE TO SAID FIRST AND SECOND CONTROL SIGNALS FOR PRODUCING ONLY DURING A FIRST OF TWO SUCCESSIVE SCAN CYCLES AN OUTPUT IN RESPONSE SOLELY TO THAT SPECIAL CONTROL SIGNAL PRODUCED DURING THE SCAN OF SAID SINGLE SLOT WITHIN SAID GIVENGROUP; A BISTABLE SWITCH COUPLED TO SAID SECOND MEANS AND SAID READOUT MEANS WHICH IS SET BY AN OUTPUT FROM SAID SECOND MEANS AND RESET IN RESPONSE TO THE SCAN OF THAT SLOT WHICH NEXT FOLLOWS SAID SINGLE SLOT OF SAID GIVEN GROUP; THIRD MEANS INCLUDING NORMALLY CLOSED ADDRESS FORWARDING MEANS COUPLED TO SAID READOUT MEANS, FOURTH MEANS AND FIFTH MEANS, SAID FOURTH MEANS COUPLED TO SAID BISTABLE SWITCH AND TO SAID STORAGE DEVICE AND RESPONSIVE TO SAID FIRST CONTROL SIGNALS AND TO SAID BISTABLE SWITCH HAVING BEEN SET AND SAID NEXT-FOLLOWING SLOT BEING OTHER THAN THE FIRST SLOT OF A GROUP FOR OPENING SAID FORWARDING MEANS TO PERMIT FORWARDING OF THE ADDRESS OF THE STATION STORED IN SAID NEXT-FOLLOWING SLOT AND FOR ALTERING THE CONTROL INFORMATION STORED IN SAID NEXT-FOLLOWING SLOT TO PROVIDE A SPECIAL CONTROL SIGNAL THEREFROM DURING SUBSEQUENT SCAN CYCLES, SAID FIFTH MEANS COUPLED TO SAID BISTABLE MEANS AND TO SAID STORAGE DEVICE AND RESPONSIVE TO SAID FIRST CONTROL SIGNALS AND TO SAID BISTABLE SWITCH HAVING BEEN SET AND SAID NEXT-FOLLOWING SLOT BEING THE FIRST SLOT OF A GROUP FOR OPENING SAID FORWARDING MEANS TO PERMIT FORWARDING THE ADDRESS OF THE STATION STORED IN THE FIRST SLOT OF SAID GIVEN GROUP DURING THE SECOND OF SAID TWO SUCCESSIVE SCAN CYCLES AND FOR ALTERING THE CONTROL INFORMATION STORED IN SAID FIRST SLOT OF SAID GIVEN GROUP TO PROVIDE A SPECIAL CONTROL SIGNAL THEREFROM DURING SUBSEQUENT SCAN CYCLES; AND SIXTH MEANS COUPLED TO SAID SECOND MEANS AND SAID STORAGE DEVICE FOR APPLYING ONLY DURING THE SECOND OF SAID TWO SUCCESSIVE SCAN CYCLES AN ERASE SIGNAL TO SAID SINGLE SLOT OF SAID GIVEN GROUP TO ALTER THE CONTROL INFORMATION STORED THEREIN TO ELIMINATE THE PROVIDING OF A SPECIAL CONTROL SIGNAL THEREFROM DURING SUBSEQUENT SCAN CYCLES.