CN212749209U - Keyboard access detection circuit and terminal equipment - Google Patents
Keyboard access detection circuit and terminal equipment Download PDFInfo
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- CN212749209U CN212749209U CN202020255649.9U CN202020255649U CN212749209U CN 212749209 U CN212749209 U CN 212749209U CN 202020255649 U CN202020255649 U CN 202020255649U CN 212749209 U CN212749209 U CN 212749209U
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Abstract
The embodiment of the utility model discloses a keyboard access detection circuit and terminal equipment, the keyboard access detection circuit is connected with a 4-pin connecting seat and a main controller, the keyboard access detection circuit comprises a detection module and a communication module, the detection module is connected with the 4-pin connecting seat and the main controller, and the communication module is connected with the 4-pin connecting seat and the main controller; when the detection module detects that the 4-pin connecting seat is connected with the keyboard to form a load loop, a detection signal in a first state is output to control the main controller to communicate with the keyboard, and the communication module filters a data signal transmitted between the main controller and the keyboard; when the detection module detects that the 4-pin connecting seat is not connected, the detection module outputs a detection signal in a second state to control the main controller to stop communication with the keyboard. Adopt 4 foot connecting seats just can realize the access detection of keyboard, need not to adopt traditional 5PIN connecting seats to solve current POGO PIN connector and adopt the great problem of 5PIN design occupation space.
Description
Technical Field
The utility model relates to the field of electronic technology, especially, relate to a keyboard inserts detection circuitry and terminal equipment.
Background
When the tablet personal computer is used as a tablet product, two schemes are provided, one scheme is that a keyboard with a leather sheath is externally connected with a USB interface of the tablet personal computer, the tablet personal computer can be used as a micro computer, but the use distance of the tablet personal computer is limited by the wired connection mode. Another kind is through POGO PIN (spring probe) connector external keyboard, however, current POGO PIN connector all is 5PIN (PINs), VCC foot, DN foot, DP foot, ID foot and GND foot promptly, and occupation space is big, has increased the overall arrangement and the cost of circuit board.
SUMMERY OF THE UTILITY MODEL
To the technical problem, the embodiment of the utility model provides a keyboard inserts detection circuitry and terminal equipment to solve current POGO PIN connector and adopt the great problem of 5PIN design occupation space.
The embodiment of the utility model provides a keyboard access detection circuit, connect 4 foot connecting seats and master controller, it includes detection module and communication module, detection module connects 4 foot connecting seats and master controller, communication module connects 4 foot connecting seats and master controller;
when the detection module detects that the 4-pin connecting seat is connected with the keyboard to form a load loop, a detection signal in a first state is output to control the main controller to communicate with the keyboard, and the communication module filters a data signal transmitted between the main controller and the keyboard;
when the detection module detects that the 4-pin connecting seat is not connected, the detection module outputs a detection signal in a second state to control the main controller to stop communication with the keyboard.
Optionally, in the keyboard access detection circuit, the detection module includes a first triode, a second triode, a first diode, a first resistor, a second resistor, and a third resistor;
the negative pole of first diode and the VCC foot of 4 foot connecting seats are connected to the base of first triode, the positive pole and the first feed end of first diode are connected to the collecting electrode of first triode, the one end of second resistance and the base of second triode are connected through first resistance to the projecting pole of first triode, the other end ground connection of second resistance, the one end and the master controller of third resistance are connected to the collecting electrode of second triode, the projecting pole ground connection of second triode, the second feed end is connected to the other end of third resistance.
Optionally, the keyboard access detection circuit, the detection module further includes a first capacitor, one end of the first capacitor is connected to the VCC pin of the 4-pin connecting base and the base of the first triode, and the other end of the first capacitor is grounded.
Optionally, in the keyboard access detection circuit, the detection module further includes a fourth resistor and a fifth resistor, one end of the fourth resistor is connected to one end of the second resistor, the other end of the fourth resistor is connected to a base of the second triode, one end of the fifth resistor is connected to a collector of the second triode, and the other end of the fifth resistor is connected to the master controller.
Optionally, in the keyboard access detection circuit, the detection module further includes a second diode, one end of the second diode is connected to the collector of the first triode and the first power supply end, and the other end of the second diode is grounded.
Optionally, in the keyboard access detection circuit, the communication module includes a filter, a third diode and a fourth diode; the 1 st pin and the 4 th pin of the filter are both connected with the master controller, the 2 nd pin of the filter is connected with one end of a fourth diode and the DM pin of the 4-pin connecting seat, and the 3 rd pin of the filter is connected with one end of a third diode and the DP pin of the 4-pin connecting seat; the other end of the third diode, the other end of the fourth diode and the GND pin of the 4-pin connecting seat are all grounded.
A second aspect of the embodiment of the present invention provides a terminal device, an external keyboard, comprising a main board, wherein the main board is provided with a main controller, wherein the main board is further provided with a 4-pin connecting seat and a keyboard access detection circuit, and the keyboard access detection circuit is connected with the 4-pin connecting seat and the main controller;
the keyboard access detection circuit detects whether the 4-pin connecting seat is externally connected with a keyboard and outputs a detection signal of a corresponding state to the main controller, and the main controller controls whether to communicate with the keyboard through the 4-pin connecting seat according to the state of the detection signal.
Optionally, in the terminal device, the 4-PIN connection base CN is a 4-PIN POGO PIN connection base including a VCC PIN, a DM PIN, a DP PIN, and a GND PIN; the interface of the keyboard comprises a VCC pin, a DM pin, a DP pin and a GND pin;
when the keyboard is externally connected, the VCC pin, the DM pin, the DP pin and the GND pin of the keyboard interface are connected with the VCC pin, the DM pin, the DP pin and the GND pin of the 4-pin connecting seat CN in a one-to-one mode.
Optionally, in the terminal device, when the 4-pin connecting seat is externally connected with the keyboard, the keyboard access detection circuit detects that the VCC pin of the 4-pin connecting seat is connected with the VCC pin of the interface of the keyboard to form a load loop, outputs a detection signal of a first state, the main controller communicates with the keyboard according to the detection signal of the first state, and the keyboard access detection circuit filters the data signal output by the main controller and outputs the data signal to the keyboard through the DP pin and the DM pin of the 4-pin connecting seat.
Optionally, in the terminal device, when the 4-pin connecting base is not connected, the keyboard access detection circuit detects that the VCC pin of the 4-pin connecting base is not connected, outputs a detection signal in the second state, and the main controller controls to stop communication with the keyboard according to the detection signal in the second state.
In the technical scheme provided by the embodiment of the utility model, the keyboard access detection circuit is connected with the 4-pin connecting seat and the main controller, and comprises a detection module and a communication module, wherein the detection module is connected with the 4-pin connecting seat and the main controller, and the communication module is connected with the 4-pin connecting seat and the main controller; when the detection module detects that the 4-pin connecting seat is connected with the keyboard to form a load loop, a detection signal in a first state is output to control the main controller to communicate with the keyboard, and the communication module filters a data signal transmitted between the main controller and the keyboard; when the detection module detects that the 4-pin connecting seat is not connected, the detection module outputs a detection signal in a second state to control the main controller to stop communication with the keyboard. Adopt 4 foot connecting seats just can realize the access detection of keyboard, need not to adopt traditional 5PIN connecting seats to solve current POGO PIN connector and adopt the great problem of 5PIN design occupation space.
Drawings
Fig. 1 is a block diagram of a terminal device according to an embodiment of the present invention.
Fig. 2 is a schematic circuit diagram of the keyboard access detection circuit in the embodiment of the present invention.
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. The embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative efforts, belong to the protection scope of the present invention.
Referring to fig. 1 and fig. 2 together, the terminal device provided in the embodiment of the present invention includes a main board, the main board is provided with a keyboard access detection circuit 10, a 4-pin connection seat CN and a main controller 20, and the keyboard access detection circuit 10 is connected with the 4-pin connection seat CN and the main controller 20; the keyboard access detection circuit 10 is used for detecting whether the 4-pin connecting seat CN is externally connected with a keyboard and outputting a detection signal of a corresponding state to the main controller 20, and the main controller 20 controls whether to communicate with the keyboard through the 4-pin connecting seat CN according to the state of the detection signal.
Wherein, 4PIN connecting seat CN is 4 feet POGO PIN connecting seat, including VCC foot, DM foot, DP foot and GND foot. Correspondingly, the interface of the external keyboard is also correspondingly set to be 4PIN, and the sequence is the same as that of the 4-PIN connecting seat CN. When the keyboard is externally connected, the VCC pin, the DM pin, the DP pin and the GND pin of the keyboard interface are connected with the VCC pin, the DM pin, the DP pin and the GND pin of the 4-pin connecting seat CN in a one-to-one mode.
When the 4-pin connecting seat is externally connected with the keyboard, the keyboard access detection circuit detects that the VCC pin of the 4-pin connecting seat is connected with the VCC pin of the interface of the keyboard to form a load loop, a detection signal of a first state is output, the main controller communicates with the keyboard according to the detection signal of the first state, and the keyboard access detection circuit filters data signals (USB2_ BT _ DM, USB2_ BT _ DP, control instructions for controlling the lightening of the keyboard and the like) output by the main controller and outputs the data signals to the keyboard through the DP pin and the DM pin of the 4-pin connecting seat. The data signal (at this time, the key command) input by the keyboard is output to the keyboard access detection circuit through the DP pin and the DM pin of the 4-pin connector to be filtered, and then the data signal (at this time, the key command) is transmitted to the main controller 20 to execute the corresponding key operation.
When the 4-pin connecting seat is not provided with the external keyboard, the keyboard access detection circuit detects that the VCC pin of the 4-pin connecting seat is not connected, outputs a detection signal of a second state, and the main controller controls the keyboard to stop communication according to the detection signal of the second state, so that no data signal is transmitted.
Compared with the existing POGO PIN connecting seat with 5 PINs, DI PIN is removed in the embodiment, and whether a load loop is formed on a VCC PIN or not is detected during detection, namely when a keyboard is connected, the keyboard is equivalent to a load, and the VCC PIN of a CN PIN connecting seat with 4 PINs is connected with the VCC PIN of an interface of the keyboard to form the load loop; when the keyboard is not connected, the VCC pin of the 4-pin connecting base CN is unloaded, and then there is no load loop. The power supply and detection functions are compatible through multiplexing the VCC PINs, the DI PIN can be saved, the design space can be reduced, the number of the PIN PINs is reduced, and the product cost is reduced.
The terminal equipment mainly is all dull and stereotyped products of taking POGO PIN connecting seat, like the panel computer, realizes the switching from the panel to miniature office computer through external keyboard. In the specific implementation, the POGO PIN connector can also be applied to other terminal equipment which is connected with a physical keyboard by using the POGO PIN connector.
Referring to fig. 2, the keyboard access detection circuit 10 includes a detection module 110 and a communication module 120, the detection module 110 is connected to the 4-pin connection socket CN and the main controller 20, the communication module 120 is connected to the 4-pin connection socket CN and the main controller 20, when the 4-pin connection socket CN is externally connected to the keyboard, the detection module 110 detects that the VCC pin of the 4-pin connection socket CN is connected to the VCC pin of the interface of the keyboard to form a load loop, outputs a detection signal in a first state (such as a high level) to control the main controller 20 to communicate with the keyboard, and the communication module 120 filters data signals (USB2_ BT _ DM and USB2_ BT _ DP) transmitted between the main controller 20 and the keyboard. When the detection module 110 detects that the VCC pin of the 4-pin connector CN is disconnected, it outputs a detection signal in a second state (e.g., low level) to control the main controller 20 to stop communication with the keyboard.
The detection module 110 comprises a first triode Q1, a second triode Q2, a first diode D1, a first resistor R1, a second resistor R2 and a third resistor R3; the base (B) of the first triode Q1 is connected with the cathode of the first diode D1 and the VCC pin of the 4-pin connection base CN, the collector (C) of the first triode Q1 is connected with the anode of the first diode D1 and the first power supply terminal (providing the first power supply voltage + DOCK _5V3, 5.3V), the emitter (E) of the first triode Q1 is connected with one end of the second resistor R2 and the base of the second triode Q2 through the first resistor R1, the other end of the second resistor R2 is grounded, the collector of the second triode Q2 is connected with one end of the third resistor R3 and the master controller 20, the emitter of the second triode Q2 is grounded, and the other end of the third resistor R3 is connected with the second power supply terminal (providing the second power supply voltage + V1P8A, 1.8V).
The first triode Q1 is a PNP triode, the second triode Q2 is an NPN triode, the first diode D1 is preferably a schottky diode of the SSCD104SH type, and the first resistor R1, the second resistor R2 and the third resistor R3 preferably have resistance values of 10K Ω.
When the keyboard (equivalent to a load) is not connected, the VCC pin of the 4-pin connecting base CN does not form a load loop, that is, the base of the Q1 has no load, no current flows through the first diode D1, at this time, the D1 is equivalent to a wire, so that the base voltage is 5.3V, at this time, the Q1 is not turned on according to the electrical characteristics of the PNP type triode, the base voltage of the Q2 is pulled down to a low level by the second resistor R2, at this time, the Q2 is not turned on according to the electrical characteristics of the NPN type triode, the collector voltage of the Q2 is pulled up to a high level by the third resistor R3, and the main controller 20 recognizes that the keyboard is not connected when detecting signal WINDOW _ contact is at the high.
When the keyboard is connected, the VCC pin, DM pin, DP pin and GND pin of the keyboard interface are connected with the VCC pin, DM pin, DP pin and GND pin of the 4-pin connecting seat CN in a one-to-one manner. The VCC pin forms a load loop, namely a base load of Q1, at the moment, current flows on the D1 and forms a voltage difference, namely, the D1 reduces 5.3V by 0.7V to enable the base voltage of the Q1 to be 4.3V, the Q1 is conducted according to the electrical characteristics of the PNP type triode, the 5.3V is changed into 5V after passing through the Q1, the voltage is divided by the first resistor R1 and the second resistor R2, the base voltage of the Q1 is changed into 2.5V, the base of the Q2 is conducted at a high level according to the electrical characteristics of the NPN type triode, the collector of the Q2 is pulled down to a low level after the Q2 is conducted, and the main controller 20 identifies that the keyboard is connected when the detection signal WINDOW _ CONTIN is at the high level.
Preferably, the detection module 110 further includes a first capacitor C1, one end of the first capacitor C1 is connected to the VCC pin of the 4-pin connector CN and the base of the first transistor Q1, and the other end of the first capacitor C1 is grounded. The voltage input by the VCC pin of the 4-pin connecting base CN is filtered through the first capacitor C1, so that the first triode Q1 is more stable when being switched on or switched off.
Preferably, the detection module 110 further includes a fourth resistor R4 and a fifth resistor R5, one end of the fourth resistor R4 is connected to one end of the second resistor R2, the other end of the fourth resistor R4 is connected to the base of the second transistor Q2, one end of the fifth resistor R5 is connected to the collector of the second transistor Q2, and the other end of the fifth resistor R5 is connected to the master 20. The second triode Q2 is current-limited and protected through a fourth resistor R4, and a fifth resistor R5 is current-limited and protects the master controller 20.
Preferably, the detection module 110 further includes a second diode D2, one end of the second diode D2 is connected to the collector (C) of the first transistor Q1 and the first power supply terminal, and the other end of the second diode D2 is grounded. The second diode D2 is an ESD (electrostatic discharge) diode for electrostatic protection and abnormal voltage protection.
The communication module 120 includes a filter CHK, a third diode D3 and a fourth diode D4; the 1 st pin and the 4 th pin of the filter CHK are both connected with the main controller 20, the 2 nd pin of the filter CHK is connected with one end of a fourth diode D4 and the DM pin of a 4-pin connecting seat CN, and the 3 rd pin of the filter CHK is connected with one end of a third diode D3 and the DP pin of the 4-pin connecting seat CN; the other end of the third diode D3, the other end of the fourth diode D4, and the GND pin of the 4-pin connector CN are all grounded.
The model of the filter CHK is preferably EXC24CE900U, and the third diode D3 and the fourth diode D4 are ESD diodes.
It should be understood that the main controller 20 (i.e., the CPU) is the prior art, and in this embodiment, which pin of the CPU is specifically connected to the 3 signals transmitted by the keyboard access detection circuit is the prior art, which is not described herein again. For example, in the prior art, the detection signal WINDOW _ contact is generated from a signal input from the DI PIN of the 5-PIN POGO PIN connecting seat (the DI PIN may be externally connected with a corresponding circuit to filter and denoise the detection signal), and is transmitted to the detection PIN of the CPU (for example, the GPIO1 PIN, which may be modified as required), while the detection signal WINDOW _ contact of the present embodiment is generated after the signal on the VCC PIN of the 4-PIN POGO PIN connecting seat is converted by the detection circuit 110, but the detection signal WINDOW _ contact is still input to the detection PIN of the CPU.
With continuing reference to fig. 1 and fig. 2, the operating principle of the terminal device is as follows:
when no external keyboard is available, the base voltage of the first triode Q1 is 5.3V, Q1 is not conducted, Q2 is not conducted, and the detection signal WINDOW _ CONTIN is pulled up to high level by R3. When the main controller 20 determines that the detection signal WINDOW _ continue is at a high level, it recognizes that there is no keyboard connection, and at this time, the main controller 20 does not communicate with the keyboard.
When the keyboard is externally connected, the VCC pin, the DM pin, the DP pin and the GND pin of the keyboard interface are connected with the VCC pin, the DM pin, the DP pin and the GND pin of the 4-pin connecting seat CN in a one-to-one mode. At this time, the keyboard is equivalent to a load, a load loop is formed, the base voltage of the Q1 is pulled down to 4.6V by the voltage drop (0.7V) of the first diode D1, the first triode Q1 is conducted to enable the emitter voltage of the Q2 to be 5V, and the Q2 is conducted to pull down the detection signal WINDOW _ control from high level to low level. When the main controller 20 determines that the detection signal WINDOW _ continue is at a low level, it recognizes that a keyboard is connected, and at this time, the main controller 20 communicates with an external keyboard through data signals (USB2_ BT _ DM, USB2_ BT _ DP), so that the tablet computer can be used as a microcomputer.
To sum up, the utility model provides a keyboard inserts detection circuitry and terminal equipment does not need special detection foot (DI PIN), adopts the POGO PIN connecting seat of 4 feet just can realize the access detection of keyboard, need not to adopt traditional 5PIN connecting seats to reach the purpose that POGO PIN keyboard does not have ID PIN and realizes the access detection and the switching between panel and the computer mode, realize the microcomputer function of dull and stereotyped product transform under the prerequisite that reduces product cost, promoted the price/performance ratio and the market competition of product.
The above embodiments are only used to illustrate the technical solution of the present invention, and not to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, it should be understood by those skilled in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; such modifications and substitutions do not depart from the spirit and scope of the present invention in its corresponding aspects.
Claims (10)
1. A keyboard access detection circuit is connected with a 4-pin connecting seat and a main controller and is characterized by comprising a detection module and a communication module, wherein the detection module is connected with the 4-pin connecting seat and the main controller, and the communication module is connected with the 4-pin connecting seat and the main controller;
when the detection module detects that the 4-pin connecting seat is connected with the keyboard to form a load loop, a detection signal in a first state is output to control the main controller to communicate with the keyboard, and the communication module filters a data signal transmitted between the main controller and the keyboard;
when the detection module detects that the 4-pin connecting seat is not connected, the detection module outputs a detection signal in a second state to control the main controller to stop communication with the keyboard.
2. The keyboard access detection circuit of claim 1, wherein the detection module comprises a first transistor, a second transistor, a first diode, a first resistor, a second resistor, and a third resistor;
the negative pole of first diode and the VCC foot of 4 foot connecting seats are connected to the base of first triode, the positive pole and the first feed end of first diode are connected to the collecting electrode of first triode, the one end of second resistance and the base of second triode are connected through first resistance to the projecting pole of first triode, the other end ground connection of second resistance, the one end and the master controller of third resistance are connected to the collecting electrode of second triode, the projecting pole ground connection of second triode, the second feed end is connected to the other end of third resistance.
3. The keyboard access detection circuit of claim 2, wherein the detection module further comprises a first capacitor, one end of the first capacitor is connected to the VCC pin of the 4-pin connection base and the base of the first triode, and the other end of the first capacitor is grounded.
4. The keyboard access detection circuit according to claim 2, wherein the detection module further comprises a fourth resistor and a fifth resistor, one end of the fourth resistor is connected to one end of the second resistor, the other end of the fourth resistor is connected to the base of the second transistor, one end of the fifth resistor is connected to the collector of the second transistor, and the other end of the fifth resistor is connected to the master controller.
5. The keyboard access detection circuit of claim 2, wherein the detection module further comprises a second diode, one end of the second diode is connected to the collector of the first transistor and the first power supply terminal, and the other end of the second diode is grounded.
6. The keyboard access detection circuit of claim 2, wherein the communication module comprises a filter, a third diode, and a fourth diode; the 1 st pin and the 4 th pin of the filter are both connected with the master controller, the 2 nd pin of the filter is connected with one end of a fourth diode and the DM pin of the 4-pin connecting seat, and the 3 rd pin of the filter is connected with one end of a third diode and the DP pin of the 4-pin connecting seat; the other end of the third diode, the other end of the fourth diode and the GND pin of the 4-pin connecting seat are all grounded.
7. A terminal device, an external keyboard, comprising a mainboard, wherein the mainboard is provided with a master controller, the terminal device is characterized in that the mainboard is also provided with a 4-pin connecting seat and a keyboard access detection circuit according to any one of claims 1-6, and the keyboard access detection circuit is connected with the 4-pin connecting seat and the master controller;
the keyboard access detection circuit detects whether the 4-pin connecting seat is externally connected with a keyboard and outputs a detection signal of a corresponding state to the main controller, and the main controller controls whether to communicate with the keyboard through the 4-pin connecting seat according to the state of the detection signal.
8. The terminal equipment according to claim 7, wherein the 4-PIN connection base CN is a 4-PIN POGO PIN connection base, comprising a VCC PIN, a DM PIN, a DP PIN and a GND PIN; the interface of the keyboard comprises a VCC pin, a DM pin, a DP pin and a GND pin;
when the keyboard is externally connected, the VCC pin, the DM pin, the DP pin and the GND pin of the keyboard interface are connected with the VCC pin, the DM pin, the DP pin and the GND pin of the 4-pin connecting seat CN in a one-to-one mode.
9. The terminal device of claim 8, wherein when the 4-pin connecting seat is externally connected to the keyboard, the keyboard access detection circuit detects that a VCC pin of the 4-pin connecting seat is connected to a VCC pin of an interface of the keyboard to form a load loop, and outputs a detection signal of a first state, the main controller communicates with the keyboard according to the detection signal of the first state, and the keyboard access detection circuit filters a data signal output by the main controller and outputs the data signal to the keyboard through a DP pin and a DM pin of the 4-pin connecting seat.
10. The terminal device of claim 8, wherein when the 4-pin connection socket is not connected, the keyboard access detection circuit detects that the VCC pin of the 4-pin connection socket is not connected, and outputs a detection signal of a second state, and the main controller controls the keyboard to stop communication according to the detection signal of the second state.
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| CN202020255649.9U CN212749209U (en) | 2020-03-05 | 2020-03-05 | Keyboard access detection circuit and terminal equipment |
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| CN202020255649.9U CN212749209U (en) | 2020-03-05 | 2020-03-05 | Keyboard access detection circuit and terminal equipment |
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113485088A (en) * | 2021-06-28 | 2021-10-08 | 上海闻泰信息技术有限公司 | Keyboard switching circuit and control method thereof |
| CN115166590A (en) * | 2022-06-29 | 2022-10-11 | 南京微智新科技有限公司 | Keyboard access detection loop and electronic equipment |
| CN115525099A (en) * | 2022-01-11 | 2022-12-27 | 荣耀终端有限公司 | Terminal equipment and method for detecting keyboard access |
-
2020
- 2020-03-05 CN CN202020255649.9U patent/CN212749209U/en active Active
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113485088A (en) * | 2021-06-28 | 2021-10-08 | 上海闻泰信息技术有限公司 | Keyboard switching circuit and control method thereof |
| CN113485088B (en) * | 2021-06-28 | 2023-03-14 | 上海闻泰信息技术有限公司 | Keyboard switching circuit and control method thereof |
| CN115525099A (en) * | 2022-01-11 | 2022-12-27 | 荣耀终端有限公司 | Terminal equipment and method for detecting keyboard access |
| CN115525099B (en) * | 2022-01-11 | 2023-08-11 | 荣耀终端有限公司 | Terminal equipment and method for detecting keyboard access |
| CN115166590A (en) * | 2022-06-29 | 2022-10-11 | 南京微智新科技有限公司 | Keyboard access detection loop and electronic equipment |
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