Computer controlled switching system using flip-flops for control of repetitive operations

Claim 2

A digital computer for controlling telephone switching systems comprising a program permanent store having written therein contingent instructions relative to telephone communication establishment and release processing operations, a readout register, an instructions address register for addressing an instruction to be readout and an auxiliary instruction address register for memorizing the address of an instruction to be readout, said readout, instructions address and auxiliary instruction address registers being associated with said program permanent store, a multiregister, write-in and rewrite-in register means for writing in said multiregister register words containing data relative to the actual state of a telephone communication being processed and for rewriting in said multiregister modified register words, a readout register associated with said multiregister, a group of flip-flops controlling, according to their relative states, repetitive operations consisting in reading out from said readout register the register words, testing the potentials of points located in said switching system, receiving test result signals from said tested points and rewriting in said write-in and reWrite-in register means the register words selectively modified according to said test result signals, first means for jumping from the control of the computer by said group of flip-flops to the control thereof by said program permanent store, said first means comprising means for comparing the result signals of two consecutive potential tests, means for counting the number of consecutive tests with unchanged result signals and means, controlled by both said comparing means and said counting means, for inhibiting said flip-flops, transferring in the instruction address register the address contained in the auxiliary instruction address register and activating the program permanent store, and second means for jumping from the control of the computer by said program permanent store to the control thereof by said group of flip-flops, said second means comprising means for detecting a jump instruction in said instruction register, transferring in the auxiliary instruction address register the address of said jump instruction, inhibiting the program permanent store and activating said group of flip-flops.

Claim 3

A digital computer for controlling telephone switching systems comprising a program permanent store having written therein contingent instructions relative to telephone communication establishment and release processing operations, each instruction being composed of a plurality of function orders, an instruction address register for addressing an instruction to be readout, an auxiliary instruction address register for memorizing the address of an instruction to be readout, a readout instruction register and a function decoder associated with said program permanent store, said function decoder being connected to said readout instruction register and delivering order signals on a plurality of output terminals, a multiregister, write-in and rewrite-in register means for writing in said multiregister register words containing data relative to the actual state of a telephone communication being processed and for rewriting in said multiregister modified register words associated with said multiregister, a group of flip-flops controlling, according to their relative states, repetitive operations consisting in reading out from said readout register the register words, testing the potentials of points located in said switching system, receiving test result signals from said tested points and rewriting in said write-in register the register words selectively modified according to said test result signals, and delivering order signals on a plurality of output terminals, the output terminals of the function decoder and the group of flip-flops delivering the same order signals being respectively connected, first means for jumping from the control of the computer by said group of flip-flops to the control thereof by said program permanent store, said first means comprising means for comparing the results of two consecutive potential tests, means for counting the number of consecutive tests with unchanged results and means, controlled by both said comparing means and said counting means, for inhibiting said flip-flops, transferring into the instruction address register the address contained in the auxiliary instruction address register and activating the program permanent store, and second means for jumping from the control of the computer by said program permanent store to the control thereof by said group of flip-flops, said second means comprising means for detecting a jump instruction in said instruction register, transferring into the auxiliary instruction address register the address of said jump instruction, inhibiting the program permanent store and activating said group of flip-flops.

Claim 4

A digital computer for controlling telephone switching systems comprising a program permanent store having written therein contingent instructions relative to telephone communication establishment and release processing operations, each instruction being composed of a plurality of function orders, an instruction address register for addressing an instruction to be readout, an auxiliary instruction address register for memorizing the address of an instruction to be readout, a readout instruction register and a function decoder associated with said program permanent store, said function decoder being connected to said readout instruction register and delivering order signals on a plurality of output terminals, a multiregister, write-in and rewrite-in register means for writing in said multiregister register words containing data relative to the actual state of a telephone communication being processed and for rewriting in said multiregister modified register words associated with said multiregister, a group of flip-flops controlling, according to their relative states, repetitive operations consisting in reading out from said readout register the register words, testing the potentials of points located in said switching system, receiving test result signals from said tested points and rewriting in said write-in register the register words selectively modified according to said test result signals, and delivering order signals on a plurality of output terminals, the output terminals of the function decoder and the group of flip-flops delivering the same order signals being respectively connected, first means for jumping from the control of the computer by said group of flip-flops to the control thereof by said program permanent store, said first means comprising means for comparing the results of two consecutive potential tests, means for counting the number of consecutive tests with unchanged results and means, controlled by both said comparing means and said counting means, for inhibiting said flip-flops, transferring into the instruction address register the address contained in the auxiliary instruction address register and activating the program permanent store, and second means for jumping from the control of the computer by said program permanent store to the control thereof by said group of flip-flops, said second means comprising means for detecting a jump instruction in said instruction register, transferring into the auxiliary instruction address register the address of said jump instruction, inhibiting the program permanent store and activating said group of flip-flops.