Switch scanning means for use with integrated circuits
AssigneeCommodore Electronics Limited
InventorTom M. Hyltin
Life of this patent
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AssigneeCommodore Electronics Limited
InventorTom M. Hyltin
Estimating the term…
Method and apparatus for generating a digital data word representative of the position of a switch element which is selectively engageable with one of a plurality of driver conductors which are utilized for conducting actuating signals from a source to a data display system of the type having a plurality of display elements for visually indicating alphanumeric data. The display elements have visually perceptible and imperceptible data indicating states and are characterized by a lagging response to either the application or interruption of the actuating signal wherein a turn-on or turn-off transition interval elapses during a change from one state to the other with the preexisting state of the display element appearing to an observer to remain unchanged during the transition interval. The actuating signals are periodically applied during a load energizing interval through one or more of the driver conductors and are interrupted during a sampling interval. The load energizing interval is much longer in duration relative to the duration of the sampling interval, with the duration of the sampling interval being substantially less than the duration of the turn-off transition interval. Each driver conductor is sequentially pulsed during the sampling interval with a strobe signal having a pulse component duration which is substantially shorter than the turn-on time of the display elements. A number of repetitive events are counted which occur during the interval commencing with the first application of a strobe pulse to a driver conductor of the array and terminating with the application of a strobe pulse to the driver conductor engaged in electrical contact with the data input conductor through the movable switch element. The number of repetitive events counted during the sampling interval is proportional to the number of strobe pulses applied to the driver conductors during the sampling interval and is therefore representative of the position of the movable switch element.
In combination:
Matrix switch apparatus comprising:
In a digital data display system of the type having a plurality of display elements for visually indicating alphanumeric data in response to an actuating signal, said display elements each having visually perceptible and imperceptible data indicating states and being characterized by a lagging response to either the application or interruption of the actuating signal wherein a turn-on or turn-off transition interval elapses during a change from one state to the other with the preexisting visual state of the display element appearing to an observer to remain unchanged during the transition interval, a data logic circuit having output nodes for driving said visual display elements and a data input node, and a plurality of driver conductors electrically connecting said data output nodes to said data display elements, the combination with said driver conductors of a data input conductor connected to said data input node, a movable switch element for electrically connecting the data input conductor to one of the driver conductors, a strobe generator electrically coupled to said driver conductors for pulsing each driver conductor with a strobe pulse having a duration which is less than the duration of the turn-on transition interval during a sampling interval having a duration which is less than the duration of the display element turn-off transition interval, a counter coupled to said strobe generator for counting the strobe pulses and producing a plurality of data bits defining a data word representative of its count, and control circuit means coupled to said data logic circuit, data input conductor and counter for interrupting the display actuating signals during said sampling interval and applying said strobe pulses to said driver conductors, starting the counting of the strobe pulses in response to the first application of a strobe pulse to a driver conductor, latching the counter and storing the data word representative of its count in response to the transmission of a strobe pulse through the data input conductor.
In apparatus having a plurality of driver conductors disposed in an array for conducting actuating signals to a group of display elements for visually indicating alphanumeric data, wherein each display element is characterized by a turn-on and turn-off transition interval, the combination with the driver conductor array of a plurality of data input conductors disposed for electrical connection with each of the primary conductors;
In apparatus having a plurality of driver conductors disposed in an array for conducting actuating signals to a group of display elements for visually indicating alphanumeric data, wherein each display element is characterized by a turn-on and turn-off transition interval during which intervals the preexisting data-indicating state appears to remain unchanged, the combination with the driver conductor array of a plurality of data input conductors disposed for electrical contact with each of the primary conductors;
In electrical apparatus having a plurality of data display elements, a data transmission circuit for generating a plurality of data signals representative of alphanumeric data, and a plurality of driver conductors interconnecting the data transmission circuit with the data display elements, the combination of a control circuit coupled to said data transmission circuit for interrupting the data signals during a scan interval having a duration which is less than the turn-off time of the data display elements, a strobe circuit coupled to said driver conductors for pulsing the driver conductors with an electrical strobe signal having a pulse duration less than the turn-on time of the data display elements, and a counting circuit coupled to said strobe circuit and to a selected one of the driver conductors for counting the number of strobe pulses applied during the scan interval commencing with the first application of a strobe pulse to a driver conductor and terminating with the application of a strobe pulse to said selected driver conductor.
A method for generating a digital data word representative of the position of a movable switch element which is selectively engageable in discrete contacting relation with one of a plurality of driver conductors which are utilized for conducting actuating signals from a source to a data display system of the type having a plurality of display elements for visually indicating alphanumeric data, each display element having visually perceptible and imperceptible data indicating states and being characterized by a lagging response to either the application or interruption of the actuating signal wherein a turn-on or turn-off transition interval elapses during a change from one state to the other with the preexisting state of the display element appearing to an observer to remain unchanged during the transition interval, said method comprising the steps:
A method for generating a digital data word representative of the row and column location of a switch element in a switch matrix having conductor elements coupled between the intersections of row and column conductors for selectively establishing a momentary electrical contact between the row and column conductors at each matrix intersection wherein said column conductors are also utilized for conducting actuating signals from a source to a data display system of the type having a plurality of display elements for visually indicating alphanumeric data, said display elements being characterized by a lagging response to either the application or interruption of the actuating signal wherein a turn-on or turn-off transition interval elapses during a change from one state to the other with the preexisting visual state continuing during the transition interval, said method comprising the steps:
Dependencies are inferred from the claim text.