Step-by-step pulse transmitter

Claim 2

A pulse transmitter comprising a counter, a pulse generator and a gate circuit, means coupling said gate circuit between said counter and said pulse generator, said gate remaining ''''off'''' when potentials representing a predetermined number are present in said counter, said counter including means to receive potentials representing numbers from another source, said gate circuit responding to potentials representing any other number in said counter to provide signals to energize said pulse generator, means coupling pulses from said pulse generator to an input terminal of said counter to step the counter until its count is restored to the predetermined number, the pulse transmitter being interconnected with a set of bistables by a data switch arranged such that a pattern of states of the bistables can be transferred into the individual storage elements of the counter by the operation of the switch, and further including interlocking means for preventing the transference of a number into the counter which would be such as to cause the pulse transmitter to generate more than ten pulses.

Claim 3

A pulse transmitter comprising a counter, a pulse generator and a gate circuit, means coupling said gate circuit between said counter and said pulse generator, said gate remaining ''''off'''' when potentials representing a predetermined number are present in said counter, said counter including means to receive potentials representing numbers from another source, said gate circuit responding to potentials representing any other number in said counter to provide signals to energize said pulse generator, means coupling pulses from said pulse generator to an input terminal of said counter to step the counter until its count is restored to the predetermined number, the pulse transmitter being interconnected with a set of bistables by a data switch arranged such that a pattern of states of the bistables can be transferred into the individual storage elements of the counter by the operation of the switch, and further including a code converter for converting a variable length serial code into a fixed length parallel code part of which code converter is formed by the set of bistables, and a code element discriminator whose output is fed to the input of the code converter.

Claim 4

A pulse transmitter comprising a counter, a pulse generator and a gate circuit, means coupling said gate circuit between said counter and said pulse generator, said gate remaining ''''off'''' when potentials representing a predetermined number are present in said counter, said counter including means to receive potentials representing numbers from another source, said gate circuit responding to potentials representing any other number in said counter to provide signals to energize said pulse generator, means coupling pulses from said pulse generator to an input terminal of said counter to step the counter until its count is restored to the predetermined number, the pulse transmitter being interconnected with a set of bistables by a data switch arranged such that a pattern of states of the bistables can be transferred into the individual storage elements of the counter by the operation of the switch, and further including a code converter for converting a variable length serial code into a fixed length parallel code part of which code converter is formed by the set of bistables, and a code element discriminator whose output is fed to the input of the code converter.

Claim 5

The combination as claimed in claim 1 wherein the bistables are interconnected to form a shift register.

Claim 6

A telephone subset including pulse generating apparatus as claimed in claim 2.

Claim 7

Pulse generating apparatus as claimed in claim 2 wherein the code element discriminator is constructed to distinguish between three code element types in accordance with prescribed signal lengths.

Claim 8

A pulse transmitter as claimed in claim 1 in which the gate circuit includes an OR gate and said OR gate is responsive to potentials in said counter representing digits other than zero to energize said pulse generator.

Claim 9

A pulse transmitter as claimed in claim 6, in which the predetermined number is zero, and the pulses from the pulse generator step the counter until its count is zero.

Claim 10

A pulse transmitter as claimed in claim 1, in which the predetermined number is zero, the counter is a four-bit binary counter responsive to receive input signals in parallel to set each bit in said counter to a particular numerical value, the gate circuit is an OR gate made conductive in response to potentials in said counter representing said particular numerical value, and the pulse generator steps the counter to the predetermined number.