ADDRESS INTERRUPT AND CURRENT STATUS DISPLAY

• US 3,806,872 A
• Filed: 05/10/1973
• Issued: 04/23/1974
• Est. Priority Date: 05/10/1973
• Status: Expired due to Term

• Current Assignee: JM Huber Corporation
• Original Assignee: James T. Odom
• Inventors: Odom, James T.
• Primary Examiner(s): Yusko, Donald J.
• Application Number:
  US05/358,862
• Time in Patent Office: 348 Days
• Field of Search: 340/152T,147R,163,167A,167R,409
• US Class Current: 340/3.51
• CPC Class Codes: G08B 26/002 only replying the state of the sensor
• CPC Class Codes: H04Q 9/14 Calling by using pulses

Abstract

A signaling system located at a central station sequentially interrogates a plurality of remotely located transponders. Means are provided for interrupting the normal addressing sequence and for interrogating any particular remote station, and for then displaying the current status of such station.

Claims

1. In a signaling system having a central station and a plurality of remote stations, said central station having means for sequentially transmitting time coded address signals to each of said remote stations in a pre-established sequence, each of said remote stations transponding to said central station upon receipt of a respective time coded address signal, the combination comprising:

a fixed frequency oscillator having a fixed frequency output;

a gate having an output terminal and first and second input terminals, said fixed frequency output being applied to the first input terminal, said fixed frequency output being coupled to said remote stations through the output terminal of said gate when said gate is enabled, said gate being enabled when an enabling pulse is applied to said second terminal, the duration of each enabling pulse establishing said time coded address signals;

enabling pulse generating means for sequentially generating enabling pulses of different durations, the output of said enabling pulse generating means being applied to said second terminal;

a first plurality of duration determining means connectable into said enabling pulse generating means for establishing the duration of said enabling pulse;

sequential switching means for sequentially connecting each of said duration determining means into said enabling pulse generating means for establishing the durations of said enabling pulse in said pre-established sequence;

a second plurality of selectable duration determining means;

means for interrupting said sequential switching means and for substituting one of said selectable duration determining means for transmitting a selected new time coded address signal; and

means after receiving a signal from a remote station transponding to said selected new time coded address signal for continuing the operation of said sequential switching means.

2. The invention as defined in claim 1 wherein said enabling pulse generating means is a one-shot multivibrator.

3. The invention as defined in claim 2 wherein said first and second pluralities of duration determining means are first and second pluralities of resistors, said resistors being connectable into the R-C network of said one-shot multivibrator for establishing the duration of its output pulse.

4. The invention as defined in claim 3 wherein said sequential switching means is an electronic switch having a stage for each of said first plurality of resistors, each of said stages of said switch sequentially establishing one of said connections in response to an update pulse, said switch recycling to the first stage after the last stage is disconnected.

5. The invention as defined in clAim 4, and a second one-shot multivibrator for generating an update pulse, the trailing edge of the output of said first one-shot multivibrator triggering said second one-shot multivibrator, said update pulse being connected to said sequential circuit means for updating said switch.

6. The invention as defined in claim 5 wherein said means for interrupting the updating of said sequential switching means and for substituting one of said selectable duration determinging means comprises:

a first normally closed switch for connecting the output from said second one-shot multivibrator to said sequential switching means for updating said sequential switching means;

a second normally closed switch connecting sequentially selected ones of said first duration determining means into the R-C network of said first one-shot multivibrator;

a third switch for connecting a selected one of said second plurality of duration determining means, said second switch being normally open;

means for opening said first and second switches and for closing said third switch; and

means for subsequently closing said first and second switches and for opening said third switch.

7. The invention as defined in claim 6 wherein an addressed remote station transponds during the period of said update pulse;

and means during the period of said update pulse for displaying a received signal from a remote station.

8. The invention as defined in claim 7 wherein said means for displaying a received signal includes a gate having an output terminal and first and second input terminals, said first input terminal being supplied with decoded received signals, said second terminal enabling said gate when supplied with a comparator output;

a comparator having first and second inputs, said first input being a manually selected numerically coded address, said second input being supplied with a numerical coded address representing a selected new time coded address signal, the output of said address comparator being applied to said terminal of said gate and enabling said gate when the numerical addresses in said comparator are in coincidence.

9. In a signaling system having a central station and a plurality of remote stations, said central station having means for sequentially transmitting time coded address signals to each of said remote stations in a pre-established sequence, each of said remote stations transponding to said central station upon receipt of a respective time coded address signal, said time coded address comprising the combination including a fixed frequency signal having a duration T1 followed by a space having a duration T2, in turn followed by a fixed frequency signal having a duration T3, durations T1 and T2 being variable in accordance with a program to generate said time coded signals in said pre-established sequence, said duration T3 being constant, the combination comprising:

a fixed frequency oscillator having a fixed frequency output;

a gate having an output terminal and first and second input terminals, said fixed frequency output being applied to said first input terminal, said fixed frequency output being coupled to said remote stations through the output terminal of said gate when said gate is enabled, said gate being enabled when an enabling pulse is applied to said second terminal;

first, second, third and fourth serially connected one-shot multivibrators, the trailing edge of the output pulse of each of said multivibrators triggering a succeeding multivibrator, the trailing edge of the output of said fourth multivibrator triggering said first multivibrator, each of said multivibrators having an R-C network, the duration of the output pulse of each multivibrator being a function of the parameters of a respective R-C network, the parameters of said third and fourth multivibrators being fixed, the parameters of said first and second one-shot multivibrators being sequentially alterable in accordance with said program, the duration of the outputs of said first, second, and third one-shot multivibrators being equal to T1, T2, and T3, respectively, the output of the fourth one-shot multivibrator having a fixed duration T4;

a first plurality of duration determining means connectable into the R-C network of said first one-shot multivibrator for establishing the durations of the output pulses therefrom;

a second plurality of duration determining means connectable into the R-C network of said second one-shot multivibrator for selectively re-establishing the durations of the output pulses therefrom;

sequential switching means for sequentially connecting each of said duration determining means of said first and second pluralities into the R-C networks of said first and second one-shot multivibrators in accordance with said program, said sequential switching means being updated by said fourth one-shot multivibrator;

a third and fourth plurality of selectable duration determining means;

means for interrupting the updating of said sequential switching means and for substituting one of said selectable duration determining means of each of said third and fourth pluralities for re-establishing a selected new time coded address signal;

means during the generation of the output pulse of said fourth one-shot multivibrator for displaying a received signal from a remote station; and

means after receiving a signal from said remote station transponding to said selected new time coded address signal for continuing the operation of said sequential switching means.

10. The invention as defined in claim 9 wherein said means for interrupting the updating of said sequential switching means and for substituting one of said selectable duration determining means comprises;

a first normally closed switch for connecting the output from said second one-shot multivibrator to said sequential switching means for updating said sequential switching means;

a second normally closed switch connecting sequentially selected ones of said first duration determining means into the R-C network of said first one-shot multivibrator;

a third switch for connecting a selected one of said second plurality of duration determining means, said second switch being normally open;

means for opening said first and second switches and for closing said third switch; and

means for subsequently closing said first and second switches and for opening said third switch.

11. The invention as defined in claim 10 wherein an addressed remote station transponds during the period of said update pulse;

and means during the period of said update pulse for displaying a received signal from a remote station.

12. The invention as defined in claim 11 wherein said means for displaying a received signal includes a gate having an output termianl and first and second input terminals, said first input terminal being supplied with decoded received signals, said second terminal enabling said gate when supplied with a comparator output;

a comparator having first and second inputs, said first input being a manually selected numerically coded address, said second input being supplied with a numerically coded address representing a selected new time coded address signal, the output of said address comparator being applied to said terminal of said gate and enabling said gate when the numerical addresses in said comparator are in coincidence.