Calculator input means to bypass conventional keyboard input

Claim 2

Apparatus for use with an electronic calculator having a keyboard switch means for actuating a first circuitry portion corresponding to a number to be used for calculation and a second circuitry portion corresponding to an arithmetic function capable of being performed by the calculator in carrying out the calculation comprising: means actuated in response to an input signal for generating a pair of output pulses; means coupled with said generating means for causing the deactuation of the same after said output pulses have been generated; means coupled with said generating means and having a pair of signal outputs for providing a pair of signals at said signal outputs thereof as a function of the generation of said output pulses; means coupled with one of the signal outputs for connecting the same to said first circuitry portion of the calculator in bypassing relationship to said keyboard switch means thereof; means coupled with the other signal output for coupling the same to the second circuitry portion of the calculator in bypassing relationship to said keyboard switch means; and means coupled with said generating means for directing an input signal thereto to thereby actuate the same.

Claim 3

Apparatus as set forth in claim 1, wherein said directing means comprises an actuatable device having a signal input and being operable to maintain an input signal applied to said generating means for a predetermined interval, and means coupled with the signal input of the device for providing an input pulse therefor.

Claim 4

Apparatus as set forth in claim 2, wherein said deactuating means is coupled to said device and is operable to deactuate the same at the end of said interval.

Claim 5

Apparatus as set forth in claim 3, wherein said deactuating means includes a comparator.

Claim 6

Apparatus as set forth in claim 1, wherein said directing means includes a mUltivibrator having a signal input and a signal output, said signal output being coupled to said generating means, and a probe coupled to the signal input of the multivibrator and being operable to provide an input pulse thereto.

Claim 7

Apparatus as set forth in claim 1, wherein said providing means includes a counter, said connecting means includes a gate, said gate being enabled when a signal is present at said one signal output of the counter.

Claim 8

Apparatus for use with an electronic calculator having a keyboard switch means for selectively actuating a plurality of first circuitry portions corresponding to respective numerals to be used for calculations and a second circuitry portion corresponding to an arithmetic function capable of being performed by the calculator in carrying out the calculations comprising: means actuated in response to an input signal for generating a pair of output pulses; means coupled with said generating means for deactuating the same after said output pulses have been generated; means coupled with said generating means and having a pair of signal outputs for providing a pair of signals at said signal outputs thereof as a function of the generation of respective output pulses of said generating means; first means coupled with one of said signal outputs and capable of being selectively enabled for connecting the same to said first circuitry portions of the calculator in bypassing relationship to said keyboard switch means; second means coupled with the other signal output for connecting the same to said second circuitry portion in bypassing relationship to said keyboard switch means; means coupled with said first means for selectively enabling the same; and means coupled with said generating means for directing an input signal thereto to thereby actuate the same.

Claim 9

Apparatus for use with an electronic calculator having a keyboard switch means for selectively actuating a plurality of first circuitry portions corresponding to respective numerals to be used for calculations and a second circuitry portion corresponding to an arithmetic function capable of being performed by the calculator in carrying out the calculations comprising: means actuated in response to an input signal for generating a pair of output pulses; means coupled with said generating means for deactuating the same after said output pulses have been generated; means coupled with said generating means and having a pair of signal outputs for providing a pair of signals at said signal outputs thereof as a function of the generation of respective output pulses of said generating means; first means coupled with one of said signal outputs and capable of being selectively enabled for connecting the same to said first circuitry portions of the calculator in bypassing relationship to said keyboard switch means; second means coupled with the other signal output for connecting the same to said second circuitry portion in bypassing relationship to said keyboard switch means; means coupled with said first means for selectively enabling the same; and means coupled with said generating means for directing an input signal thereto to thereby actuate the same.

Claim 10

Apparatus as set forth in claim 7, wherein said first means includes a plurality of gates, there being a gate for each first circuitry portion, respectively, each gate having a signal input coupled to said one signal output.

Claim 11

Apparatus as set forth in claim 7, wherein said calculator has a pair of second circuitry portions corresponding to a pair of arithmetic functions capable of being alternately performed by the calculator, said second means including a pair of gates capable of being enabled, each gate having a signal input coupled with said other signal output, and including means for selectively enabling said gates.

Claim 12

Apparatus as set forth in claim 7, wherein said enabling means includes a selector switch.

Claim 13

Apparatus for use with an electronic calculator having a keyboard switch means for selectively actuating a plurality of first circuitry portions corresponding to respective numerals to be used for calculations and a pair of second circuitry portions corresponding to respective arithmetic functions capable of being performed by the calculator in carrying out the calculations comprising: a pulse generator having a signal input and a signal output; an actuatable multivibrator coupled to the signal input of said pulse generator for triggering the same to cause the pulse generator to generate a series of output pulses; means coupled with said multivibrator for actuating the same; means responsive to said output pulses generated by said generating means for deactuating said multivibrator after a predetermined number of output pulses have been generated; a counter having a signal input coupled to said pulse generator and a pair of signal outputs, said counter being operable to successively provide output signals at the signal outputs thereto in response to the generation of said output pulses; a plurality of first gates, there being a first gate for each first circuitry portion of the calculator, respectively, each first gate having an input coupled to one of the signal outputs of the counter and an output adapted to be coupled with a respective first circuitry portion, whereby an input signal can be directed to the first circuitry portion in bypassing relaTionship to the keyboard switch means; means coupled with said first gates for selectively enabling the same; a pair of second gates, there being a second gate for each second circuitry portion respectively, each second gate having an input coupled to the other signal output of the counter and an output adapted to be coupled with a respective second circuitry portion, whereby an input signal can be directed to the second circuitry portion in bypassing relationship to the keyboard switch means; and means coupled with said second gates for selectively enabling the same.

Claim 14

Apparatus for use with an electronic calculator having a keyboard switch means for selectively actuating a plurality of first circuitry portions corresponding to respective numerals to be used for calculations and a pair of second circuitry portions corresponding to respective arithmetic functions capable of being performed by the calculator in carrying out the calculations comprising: a pulse generator having a signal input and a signal output; an actuatable multivibrator coupled to the signal input of said pulse generator for triggering the same to cause the pulse generator to generate a series of output pulses; means coupled with said multivibrator for actuating the same; means responsive to said output pulses generated by said generating means for deactuating said multivibrator after a predetermined number of output pulses have been generated; a counter having a signal input coupled to said pulse generator and a pair of signal outputs, said counter being operable to successively provide output signals at the signal outputs thereto in response to the generation of said output pulses; a plurality of first gates, there being a first gate for each first circuitry portion of the calculator, respectively, each first gate having an input coupled to one of the signal outputs of the counter and an output adapted to be coupled with a respective first circuitry portion, whereby an input signal can be directed to the first circuitry portion in bypassing relaTionship to the keyboard switch means; means coupled with said first gates for selectively enabling the same; a pair of second gates, there being a second gate for each second circuitry portion respectively, each second gate having an input coupled to the other signal output of the counter and an output adapted to be coupled with a respective second circuitry portion, whereby an input signal can be directed to the second circuitry portion in bypassing relationship to the keyboard switch means; and means coupled with said second gates for selectively enabling the same.

Claim 15

Apparatus as set forth in claim 11, wherein said enabling means for said first gates includes a first selector switch and said enabling means for said second gates includes a second selector switch.

Claim 16

Apparatus as set forth in claim 11, wherein said means for actuating the multivibrator includes a number of probe input terminals and a buffer coupling each terminal to the input of the multivibrator, said enabling means for said first gates being operable to selectively enable the probes coupled with said terminals.

Claim 17

In combination: an electronic calculator having a keyboard switch means and provided with a plurality of first electronic circuitry portions corresponding to respective numerals to be used for calculations and a pair of second electronic circuitry portions corresponding to arithmetic functions capable of being performed by the calculator in carrying out the calculations, each circuitry portion having a signal input; means for generating a pair of output pulses each time an input pulse is received thereby; means coupled with the generating means for applying a number of input pulses thereto to thereby actuate the same a number of times; means coupled with the generating means for successively directing said output pulses generated for each input pulse to the signal inputs of said first and second circuitry portions of the calculator in bypassing relationship to the keyboard switch means, said directing means including first means coupled with said first circuitry portions for selectively enabling the same and second means coupled with said second circuitry portions for selectively enabling the same.

Claim 18

In combination: an electronic calculator having a keyboard switch means and provided with a plurality of first electronic circuitry portions corresponding to respective numerals to be used for calculations and a pair of second electronic circuitry portions corresponding to arithmetic functions capable of being performed by the calculator in carrying out the calculations, each circuitry portion having a signal input; means for generating a pair of output pulses each time an input pulse is received thereby; means coupled with the generating means for applying a number of input pulses thereto to thereby actuate the same a number of times; means coupled with the generating means for successively directing said output pulses generated for each input pulse to the signal inputs of said first and second circuitry portions of the calculator in bypassing relationship to the keyboard switch means, said directing means including first means coupled with said first circuitry portions for selectively enabling the same and second means coupled with said second circuitry portions for selectively enabling the same.

Claim 19

The combination as set forth in claim 14, wherein said first enabling means includes a plurality of gates, there being a gate for each first circuitry portion, respectively, and a selector switch coupled with said gates for selectively enabling the latter.

Claim 20

Apparatus as set forth in claim 14, wherein said second enabling means includes a pair of gates, there being a gate for each second circuitry portion, respectively, and a selector switch coupled with said gates for selectively enabling the same.

Claim 21

Apparatus as set forth in claim 14, wherein said calculator has a housing, said generating means, said directing means, and the enabling means for each of said first and second circuitry portions, respectively, being disposed within said housing.

Claim 22

Apparatus as set forth in claim 17, wherein said applying means includes a multivibrator within said housing, a probe input terminal, and a signal input probe externally of the housing and capable of being coupled to the terminal.

Claim 23

Apparatus as set forth in claim 17, wherein said housing has a control panel, said keyboard switch means having manually actuated keys mounted on said panel, said enabling means for each of said first and second circuitry portions, respectively, including a selector switch, the selector switches being mounted on the panel.

Claim 24

In combination: an electronic calculator having a housing, a control panel, a keyboard switch means on said panel and electronic circuitry within the housing, said circuitry including a plurality of first circuitry portions corresponding to respective numerals to be used for calculations and a pair of second electronic circuitry portions corresponding to arithmetic functions capable of being performed by the calculator in carrying out the calculaTions, each circuitry portion having a signal input; a pulse generator within the housing; a multivibrator coupled to the pulse generator for triggering the same to cause the pulse generator to generate a series of output pulses; means coupled with said multivibrator and responsive to said output pulses for deactuating the multivibrator after a predetermined number of output pulses have been generated; a counter within the housing and having a signal input coupled to said pulse generator and a pair of signal outputs, said counter being operable to successively provide output signals at the signal outputs thereof in response to the generation of said output pulses; a plurality of first gates, there being a first gate for each first circuitry portion, respectively, each first gate having an input coupled to one of the signal outputs of the counter and an output coupled with the signal input of a respective first circuitry portion, whereby signals from said one signal output of the counter can be directed to the first circuitry portions in bypassing relationship to the keyboard switch means; means on the control panel for selectively enabling the first gates; a pair of second gates, there being a second gate for each second circuitry portion, respectively each second gate having an input coupled to the other signal output of the counter and an output coupled with the signal input of a respective second circuitry portion, whereby signals at the other signal output of the counter can be directed to the second circuitry portions in bypassing relationship to the keyboard switch means; means carried by the panel for selectively enabling the second gates; a number of probe input terminals extending through the housing; and means coupling said terminals with the input of the multivibrator, whereby the latter will be actuated by a pulse from a probe connected to one of the terminals.

Claim 25

In combination: an electronic calculator having a housing, a control panel, a keyboard switch means on said panel and electronic circuitry within the housing, said circuitry including a plurality of first circuitry portions corresponding to respective numerals to be used for calculations and a pair of second electronic circuitry portions corresponding to arithmetic functions capable of being performed by the calculator in carrying out the calculaTions, each circuitry portion having a signal input; a pulse generator within the housing; a multivibrator coupled to the pulse generator for triggering the same to cause the pulse generator to generate a series of output pulses; means coupled with said multivibrator and responsive to said output pulses for deactuating the multivibrator after a predetermined number of output pulses have been generated; a counter within the housing and having a signal input coupled to said pulse generator and a pair of signal outputs, said counter being operable to successively provide output signals at the signal outputs thereof in response to the generation of said output pulses; a plurality of first gates, there being a first gate for each first circuitry portion, respectively, each first gate having an input coupled to one of the signal outputs of the counter and an output coupled with the signal input of a respective first circuitry portion, whereby signals from said one signal output of the counter can be directed to the first circuitry portions in bypassing relationship to the keyboard switch means; means on the control panel for selectively enabling the first gates; a pair of second gates, there being a second gate for each second circuitry portion, respectively each second gate having an input coupled to the other signal output of the counter and an output coupled with the signal input of a respective second circuitry portion, whereby signals at the other signal output of the counter can be directed to the second circuitry portions in bypassing relationship to the keyboard switch means; means carried by the panel for selectively enabling the second gates; a number of probe input terminals extending through the housing; and means coupling said terminals with the input of the multivibrator, whereby the latter will be actuated by a pulse from a probe connected to one of the terminals.

Claim 26

The combination as set forth in claim 20, wherein is included means connecting said coupling means with the enabling means for said first gates and being operable to selectively enable the probes of at least certain of the terminals, and including a probe for each of the terminals, respectively.

Claim 27

Apparatus for use with an electronic calculator having a keyboard switch means for actuating a first circuitry portion corresponding to a number to be used for calculation and a second circuitry portion corresponding to an arithmetic function capable of being performed by the calculator in carrying out the calculation comprising: means actuated in response to an input signal for generating a pair of output pulses; means having a buffer and coupled with said generating means for directing an input signal thereto to actuate the same; means coupled with said generating means for deactuating the same after said output pulses have been generated; means coupled with said generating means and having a pair of signal outputs for providing a pair of signals at said signal outputs thereof as a function of the generation of said output pulses; means coupled with one of the signal outputs for connecting the same to said first circuitry portion of the calculator in bypassing relationship to said keyboard switch means thereof; and means coupled with the other signal output for coupling the same to the second circuitry portion of the calculator in bypassing relationship to said keyboard switch means.

Claim 28

Apparatus for use with an electronic calculator having a keyboard switch means for actuating a first circuitry portion corresponding to a number to be used for calculation and a second circuitry portion corresponding to an arithmetic function capable of being performed by the calculator in carrying out the calculation comprising: means actuated in response to an input signal for generating a pair of output pulses; means having a buffer and coupled with said generating means for directing an input signal thereto to actuate the same; means coupled with said generating means for deactuating the same after said output pulses have been generated; means coupled with said generating means and having a pair of signal outputs for providing a pair of signals at said signal outputs thereof as a function of the generation of said output pulses; means coupled with one of the signal outputs for connecting the same to said first circuitry portion of the calculator in bypassing relationship to said keyboard switch means thereof; and means coupled with the other signal output for coupling the same to the second circuitry portion of the calculator in bypassing relationship to said keyboard switch means.

Claim 29

Apparatus as set forth in claim 22, wherein said buffer includes first means for receiving a plurality of input pulses, at a first rate, and second means for applying a plurality of output pulses to the generating means with the last-mentioned output pulses being equal in number to the last-mentioned input pulses at a second rate less than said first rate.

Claim 30

Apparatus as set forth in claim 23, wherein said first means includes a first counter, said second means including a second counter, a comparator for comparing the counts of the first and second counters, a source of pulses, and means for gating the pulsEs to said generating means until a comparison of the counts of said counters is found by said comparator.

Claim 31

Apparatus as set forth in claim 24, wherein said generating means includes a multivibrator having an input and an output, means connecting the output of the multivibrator to the input of the second counter, said gating means being connected to the input of said multivibrator, and a data input terminal connected to the input of the first counter.

Claim 32

Apparatus for use with an electronic calculator having a keyboard switch means and signal input means coupled with the switch means for receiving successive signals therefrom including a first signal representing a number to be used in a calculation and a second signal representing an arithmetic function capable of being performed by the calculator in carrying out the calculation comprising: means having a signal input for generating a series of output pulses for each input pulse received at said signal input; means coupled with said signal input for directing an input pulse thereto; first means coupled with the generating means and adapted to be coupled with said signal input means for coupling a first of the output pulses to said signal input means in bypassing relationship to said keyboard switch means; and second means coupled with said generating means and adapted to be coupled with said signal input means for coupling a second output pulse to said signal input means in bypassing relationship to said keyboard switch means, whereby the first and second output pulses can be used to represent, respectively, a number to be used in a calculation by the calculator and an arithmetic function to be performed by the calculator in carrying out the calculation.

Claim 33

Apparatus for use with an electronic calculator having a keyboard switch means and signal input means coupled with the switch means for receiving successive signals therefrom including a first signal representing a number to be used in a calculation and a second signal representing an arithmetic function capable of being performed by the calculator in carrying out the calculation comprising: means having a signal input for generating a series of output pulses for each input pulse received at said signal input; means coupled with said signal input for directing an input pulse thereto; first means coupled with the generating means and adapted to be coupled with said signal input means for coupling a first of the output pulses to said signal input means in bypassing relationship to said keyboard switch means; and second means coupled with said generating means and adapted to be coupled with said signal input means for coupling a second output pulse to said signal input means in bypassing relationship to said keyboard switch means, whereby the first and second output pulses can be used to represent, respectively, a number to be used in a calculation by the calculator and an arithmetic function to be performed by the calculator in carrying out the calculation.

Claim 34

Apparatus as set forth in claim 26, when said directing means for the first output pulse and the directing means for the second output pulse include a counter coupled to the generating means and having at least a pair of output terminals, the output terminals adapted to be coupled to said signal input means of the calculator.

Claim 35

Apparatus for use with an electronic calculator having a keyboard switch means for actuating a first circuitry portion corresponding to a number to be used for a calculation and a second circuitry portion corresponding to an arithmetic function capable of being performed by the calculator in carrying out the calculation comprising: means having a signal input for generating a series of output pulses in response to the reception of an input signal at the signal input thereof; means coupled with said generating means for directing an input signal thereto to thereby cause generation of said series of output pulses; means coupled with the generating means for directing at least one of the output pulses generated thereby to said first circuitry portion of the calculator in bypassing relationship to said keyboard switch means thereof; and means coupled with the generating means for directing at least one other output pulse to the second circuitry portion of the calculator in bypassing relationship to said keyboard switch means.

Claim 36

Apparatus for use with an electronic calculator having a keyboard switch means for actuating a first circuitry portion corresponding to a number to be used for a calculation and a second circuitry portion corresponding to an arithmetic function capable of being performed by the calculator in carrying out the calculation comprising: means having a signal input for generating a series of output pulses in response to the reception of an input signal at the signal input thereof; means coupled with said generating means for directing an input signal thereto to thereby cause generation of said series of output pulses; means coupled with the generating means for directing at least one of the output pulses generated thereby to said first circuitry portion of the calculator in bypassing relationship to said keyboard switch means thereof; and means coupled with the generating means for directing at least one other output pulse to the second circuitry portion of the calculator in bypassing relationship to said keyboard switch means.

Claim 37

Apparatus as set forth in claim 28, wherein the directing means for the one output pulse and the directing means for the other output pulse include a counter having an input terminal and a pair of output terminals, the input terminal of the counter being coupled to the generating means and the output terminals adapted to be coupled to the first and second circuitry portions, respectively.

Claim 38

Apparatus as set forth in claim 28, wherein said generating means includes a comparator which limits the output pulses to a predetermined number in response to each input pulse thereof.

Claim 39

Apparatus for use with an electronic calculator having a keyboard switch means for selectively actuating a plurality of first circuitry portions corresponding to respective numerals to be used for calculations, a second circuitry portion corresponding to a control function capable of being performed by the calculator, and a third circuitry portion corresponding to an arithmetic function capable of being performed by the calculator comprising: means actuated in response to an input signal for generating a series of output pulses; first means coupled with the generating means and capable of being selectively enabled for directing a first of said output pulses corresponding to an input pulse to the first circuitry portion in bypassing relationship to said keyboard switch means; second means coupled with the generating means and capable of being selectively enabled for directing said first output pulse to the second circuitry portion; third means coupled with the first means and said second means for selectively enabling the same, whereby the first output pulse can be used to actuate either the first circuitry portion or the second circuitry portion; and fourth means coupled with the generating means for directing a second of said output pulses corresponding to an input pulse to the third circuitry portion in bypassing relationship to said keyboard switch means.

Claim 40

Apparatus for use with an electronic calculator having a keyboard switch means for selectively actuating a plurality of first circuitry portions corresponding to respective numerals to be used for calculations, a second circuitry portion corresponding to a control function capable of being performed by the calculator, and a third circuitry portion corresponding to an arithmetic function capable of being performed by the calculator comprising: means actuated in response to an input signal for generating a series of output pulses; first means coupled with the generating means and capable of being selectively enabled for directing a first of said output pulses corresponding to an input pulse to the first circuitry portion in bypassing relationship to said keyboard switch means; second means coupled with the generating means and capable of being selectively enabled for directing said first output pulse to the second circuitry portion; third means coupled with the first means and said second means for selectively enabling the same, whereby the first output pulse can be used to actuate either the first circuitry portion or the second circuitry portion; and fourth means coupled with the generating means for directing a second of said output pulses corresponding to an input pulse to the third circuitry portion in bypassing relationship to said keyboard switch means.

Claim 41

In combination: an electronic calculator having a keyboard switch means and a signal input means coupled with the switch means for receiving input signals therefrom including a first signal representing a number to be entered the calculator for use in calculations and a second signal to be used to actuate an arithmetic function of the calculator in carrying out the calculation; means independent of said keyboard switch means and responsive to an input pulse for generating a number of output pulses; first means responsive to a first of the output pulses for directing the same to the signal input means in bypassing relationship to the keyboard switch means; and second means responsive to a second of said output pulses corresponding to each input pulse for directing the other output pulses to the signal input means in bypassing relationship to said keyboard switch means, whereby the first and second output pulses can be used, respectively, to represent a number to be entered into the calculator for use in calculations and an arithmetic function to be performed by the calculator in carrying out the calculation.

Claim 42

In combination: an electronic calculator having a keyboard switch means and a signal input means coupled with the switch means for receiving input signals therefrom including a first signal representing a number to be entered the calculator for use in calculations and a second signal to be used to actuate an arithmetic function of the calculator in carrying out the calculation; means independent of said keyboard switch means and responsive to an input pulse for generating a number of output pulses; first means responsive to a first of the output pulses for directing the same to the signal input means in bypassing relationship to the keyboard switch means; and second means responsive to a second of said output pulses corresponding to each input pulse for directing the other output pulses to the signal input means in bypassing relationship to said keyboard switch means, whereby the first and second output pulses can be used, respectively, to represent a number to be entered into the calculator for use in calculations and an arithmetic function to be performed by the calculator in carrying out the calculation.

Claim 43

Apparatus as set forth in claim 32, wherein said generating means includes a pulse generator having output means at which a number of output signals are applied when an input signal is received thereby, means for deactuating the pulse generator after said output signals have been generated, a counter having a signal input coupled with the output means of the pulse generator and a number of outputs coupled with said first means and said second means, said counter being operable to provide said output pulses in response to successive input pulses received at the signal input thereof.

Claim 44

In combination: an electronic calculator having a keyboard switch means for selectively actuating a plurality of first circuitry portions corresponding to respective numerals to be used for calculations, at least one second circuitry portion corresponding to a control function capable of being performed by the calculator, and a third circuitry portion corresponding to an arithmetic function capable of being performed by the calculator; means actuated in response to an input signal for generating a series of output pulses; first means for each first circuitry portion, respectively, each first means being coupled with the generating means and capable of being selectively enabled for directing a first of said output pulses corresponding to an input pulse to its respective first circuitry portion in bypassing relationship to said keyboard switch means; second means coupled with said generating means and capable of being selectively enabled for directing said first output pulse to the second circuitry portion; third means coupled with each first means and the second means for selectively enabling either a first means or said second means, whereby the first output pulse can be used to actuate either a first circuitry portion or the second circuitry portion; and fourth means coupled with the generating means for directing a second of said output pulses corresponding to an input pulse to the third circuitry portion in bypassing relationship to said keyboard switch means.

Claim 45

In combination: an electronic calculator having a keyboard switch means for selectively actuating a plurality of first circuitry portions corresponding to respective numerals to be used for calculations, at least one second circuitry portion corresponding to a control function capable of being performed by the calculator, and a third circuitry portion corresponding to an arithmetic function capable of being performed by the calculator; means actuated in response to an input signal for generating a series of output pulses; first means for each first circuitry portion, respectively, each first means being coupled with the generating means and capable of being selectively enabled for directing a first of said output pulses corresponding to an input pulse to its respective first circuitry portion in bypassing relationship to said keyboard switch means; second means coupled with said generating means and capable of being selectively enabled for directing said first output pulse to the second circuitry portion; third means coupled with each first means and the second means for selectively enabling either a first means or said second means, whereby the first output pulse can be used to actuate either a first circuitry portion or the second circuitry portion; and fourth means coupled with the generating means for directing a second of said output pulses corresponding to an input pulse to the third circuitry portion in bypassing relationship to said keyboard switch means.