CN209803294U

CN209803294U - Detection apparatus for matrix button

Info

Publication number: CN209803294U
Application number: CN201920470714.7U
Authority: CN
Inventors: 孙超; 张文斌; 耿士华
Original assignee: Shandong Chaoyue CNC Electronics Co Ltd
Current assignee: Shandong Chaoyue CNC Electronics Co Ltd
Priority date: 2019-04-09
Filing date: 2019-04-09
Publication date: 2019-12-17
Anticipated expiration: 2029-04-09

Abstract

The utility model discloses a detection device of matrix button, including microprocessor, microprocessor is equipped with the AD interface that has AD conversion function, the matrix button system electric connection that AD interface and a plurality of button SW are constituteed, matrix button system power supply one end is equipped with current-limiting resistor, be equipped with expander circuit and first divider resistor behind the current-limiting resistor, it has button SW to establish ties behind the first divider resistor, constitute a passageway, insert the passageway combination of a plurality of second divider resistors and button SW as required behind the first divider resistor, AD interface produces different voltage values when button SW is closed, microprocessor determines current button SW is closed through detecting voltage value; the utility model realizes that a large number of IO interfaces are released, the limitation of the number of pins of the processor is avoided, the circuit is simplified, and the device occupies less system resources; the voltage dividing resistor is a precision resistor, so that the voltage value at the AD interface is accurate, and the detection precision is high; the divider resistor and the key SW form a path independently, and the extension is easy.

Description

Detection apparatus for matrix button

Technical Field

The utility model relates to a circuit design technical field, concretely relates to detection apparatus of matrix button.

Background

Along with the development of scientific technology, many production and living demands are brought forth in the field of novel electronic products, so more and more electronic products are produced, in the design process of the products, an important technology is a design method of a man-machine interaction interface, when a product needs to be provided with a plurality of keys, key information is detected to become an important design field, the traditional key matrix monitoring method is that a plurality of groups of IO ports are used for connecting different keys, different IO interfaces are respectively scanned by adopting a line and column scanning method in a controller, when the corresponding line and column level changes are scanned, the fact that the corresponding keys are pressed can be judged, the technology needs to occupy more IO resources of a processor, meanwhile, programs of a key detection part can occupy a large amount of computing resources due to repeated scanning of the IO port information, so that the method puts higher requirements on the selection of the processor, it is not favorable to realize the key detection function with low cost.

SUMMERY OF THE UTILITY MODEL

To the problem that exists among the prior art, the utility model aims to provide a detection device of matrix button.

the utility model provides a technical scheme that its technical problem adopted is: the utility model provides a detection apparatus for matrix button, including microprocessor, microprocessor is equipped with the AD interface that has AD conversion function, the matrix button system electric connection that AD interface and a plurality of button SW are constituteed, matrix button system power supply one end is equipped with current-limiting resistor, be equipped with expander circuit and first divider resistor behind the current-limiting resistor, it has button SW to establish ties behind the first divider resistor, constitute a route, insert the route combination of a plurality of second divider resistors and button SW behind the first divider resistor as required, AD kneck produces different voltage values when button SW is closed, microprocessor confirms that current button SW is closed through the detected voltage value.

Preferably, the second voltage-dividing resistor and the key SW are connected in series in a combined way as required, so that a simple extended circuit is realized, and the voltage value is kept unchanged when the original key SW is closed.

Preferably, the resistances between the AD interface and the key SW are different, when the key is closed, the voltages generated at the AD interface are different, and the microprocessor detects the different voltages to determine that the key SW is closed.

Preferably, the voltage value at the AD interface is consistent with the power supply voltage when the key SW is disconnected; when the microprocessor detects the voltage value change at the AD interface, the microprocessor judges the voltage value, and the voltage value detected when the nth key SW is pressed is 1/(n-1) of the power voltage; when the key SW is turned off, the voltage value at the AD interface is consistent with the power supply voltage again.

The utility model discloses following beneficial effect has:

1. The utility model discloses be equipped with microprocessor and AD interface structure, realized having released a large amount of IO interfaces, not received the restriction of treater pin quantity, the circuit obtains simplifying, and the device occupies system resource less.

2. The utility model discloses be equipped with divider resistance and be accurate resistance, obtain stable voltage through the divider resistance passageway, AD kneck voltage value is accurate, and the device detects the accuracy height.

3. The utility model discloses be equipped with divider resistance and button SW and form the route alone, the device easily expands.

Drawings

fig. 1 is a frame diagram of a detection device for matrix keys.

Fig. 2 is a circuit diagram of a detection device for matrix keys.

Detailed Description

The technical solutions in the embodiments of the present invention will be described clearly and completely with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative work belong to the protection scope of the present invention.

As shown in fig. 1, a detection device for a matrix key, which comprises a microprocessor, the microprocessor is provided with an AD interface having an AD conversion function, the AD interface is electrically connected with a matrix key system composed of a plurality of keys SW, a current-limiting resistor is arranged at a power supply end of the matrix key system, an expansion circuit and a first divider resistor are arranged behind the current-limiting resistor, a key SW is connected in series behind the first divider resistor to form a channel, a plurality of second divider resistors and a key SW channel combination are connected as required behind the first divider resistor, different voltage values are generated at the AD interface when the key SW is closed, and the microprocessor determines that the current key SW is closed through detecting the voltage values.

The serial channel combination of the second voltage-dividing resistor and the key SW is accessed as required, so that a simple circuit expansion is realized, and the voltage value is kept unchanged when the original key SW is closed; the resistance values of the AD interface and the key SW are different, when the key is closed, the voltage values generated at the AD interface are different, and the microprocessor detects different voltage values to determine that the key SW is closed.

The voltage value at the AD interface is consistent with the power voltage when the key SW is switched off; when the microprocessor detects the voltage value change at the AD interface, the microprocessor judges the voltage value, and the voltage value detected when the nth key SW is pressed is 1/(n-1) of the power voltage; when the key SW is turned off, the voltage value at the AD interface is consistent with the power supply voltage again.

It is noted that, herein, relational terms such as first and second, and the like may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus.

Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that changes, modifications, substitutions and alterations can be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the appended claims and their equivalents.

Claims

1. A detection device for matrix keys comprises a microprocessor, and is characterized in that: the microprocessor is provided with an AD interface with an AD conversion function, the AD interface is electrically connected with a matrix key system formed by a plurality of keys SW, one end of the matrix key system for supplying power is provided with a current-limiting resistor, an expansion circuit and a first divider resistor are arranged behind the current-limiting resistor, the keys SW are connected in series behind the first divider resistor to form a channel, the channels of the second divider resistors and the keys SW are connected into the first divider resistor as required, different voltage values are generated at the AD interface when the keys SW are closed, and the microprocessor determines that the current keys SW are closed by detecting the voltage values.

2. A matrix key detection device according to claim 1, characterized in that: and the second voltage-dividing resistor and the key SW are connected in series in a way of combining the channels as required, so that a simple circuit expansion is realized, and the voltage value is kept unchanged when the original key SW is closed.

3. A matrix key detection device according to claim 1, characterized in that: the resistance values of the AD interface and the key SW are different, when the key is closed, the voltage values generated at the AD interface are different, and the microprocessor detects the different voltage values to determine that the key SW is closed.

4. A matrix key detection device according to claim 3, wherein: the voltage value at the AD interface is consistent with the power voltage when the key SW is switched off;

When the microprocessor detects the voltage value change at the AD interface, the microprocessor judges the voltage value, and the voltage value detected when the nth key SW is pressed is 1/(n-1) of the power voltage;

when the key SW is turned off, the voltage value at the AD interface is consistent with the power supply voltage again.