Magnetic axis keyboard Hall sensor array reading circuit and reading method

Abstract

The invention discloses a magnetic axis keyboard Hall sensor array reading circuit and a reading method. The device comprises a Hall sensor array, a controllable power supply array, a control module, two 1-out-of-N selectors, an analog comparator, a digital comparator, an analog-to-digital converter and a digital-to-analog converter. The power supply end of each Hall sensor is connected with the output end of the corresponding controllable power supply, and signals input by the high-voltage enabling end and the low-voltage enabling end of each controllable power supply are not high levels at the same time. A mobile threshold register and a trigger threshold register are arranged in the control module, output ends of the N Hall sensors are respectively connected with corresponding input ends of the two one-out-of-N selectors, and the two one-out-of-N selectors are respectively connected with the mobile threshold register and the trigger threshold register through the analog comparator and the digital comparator. According to the invention, adaptive frequency modulation and voltage regulation can be carried out, the working current of the Hall sensor array is greatly reduced, the working time of the magnetic axis keyboard is prolonged, and the key delay is reduced.

Description

Technical Field

[0001] This invention belongs to the field of signal sampling technology, specifically relating to a low-power magnetic axis keyboard Hall sensor array readout circuit and readout method. Background Technology

[0002] Hall effect sensors operate based on the Hall effect, generating electrical signals through changes in magnetic fields. They are widely used in industrial, automotive, and consumer electronics fields. The power consumption of a Hall sensor primarily comes from the Hall element and signal processing circuitry. Because the output amplitude of a Hall sensor is proportional to the current, its operating power consumption is typically relatively high. Reducing the operating power consumption of Hall sensors is a key technical challenge for improving the battery life of battery-powered devices and meeting the low-power requirements of IoT terminals. Switch-type Hall circuits periodically detect the magnetic field, waking up the main sensor when it exceeds a threshold; reducing the duty cycle can significantly reduce power consumption. For linear Hall sensors, power consumption can also be reduced by lowering the operating voltage or turning off the power supply when not detecting.

[0003] On a magnetic axis keyboard, each key corresponds to a Hall sensor, and a keyboard may have 88 or more Hall sensors. This results in considerable power consumption. Current methods scan keys by periodic measurement. When a key needs to be scanned, the corresponding Hall sensor is powered on, and after a settling time, the output of that Hall sensor is measured. Then, the power to the Hall sensor is turned off. It takes approximately 10-20 microseconds from powering on the Hall sensor to its output stabilizing. For example, patent application number 202510645689.1 discloses a Hall circuit and Hall chip, which uses a magnetoresistive sensor to control the Hall module to turn on the working mode to reduce the working current; patent application number 202411892413.5 proposes a method to provide a constant current to the Hall circuit using a constant current source; patent application number 202411221757.3 proposes that when a key on a magnetic axis keyboard is not pressed, the magnetic sensor corresponding to the key is in a non-working state to reduce power consumption; patent application number 202422042023.0 proposes to use a metal shell with a sensing component inside, which is used to sense the human body and can stop scanning in the sleep state, thereby reducing the power consumption of the magnetic axis keyboard; and patent application number 202323088778.6 uses a specific key to change the keyboard's sleep state and reduce the sleep current.

[0004] Utility model patent No. 202322865453.8 discloses a magnetic axis keyboard that reduces sleep current. It uses a magnetic axis sleep Hall effect sensor switch to connect to the sleep circuit of the main control chip, avoiding the need for the main control chip to scan all the magnetic axis Hall effect sensors. Since periodic scanning of the keyboard array is required, reducing key scanning latency and improving key response speed are also important requirements for keyboards. For example, invention patent application No. 202510119011.X discloses a three-mode magnetic axis keyboard system, proposing a switch array; invention patent application No. 202510383314.2 discloses a magnetic axis keyboard, proposing a method for improving speed using a multi-level microcontroller. Summary of the Invention

[0005] One objective of this invention is to propose a low-power magnetic axis keyboard Hall sensor array readout circuit based on periodic sampling, addressing the limitations of existing magnetic axis keyboards.

[0006] The present invention includes a Hall sensor array, a controllable power supply array, a control module U, two N-to-1 selectors, an analog comparator, a digital comparator, an analog-to-digital converter, and a digital-to-analog converter.

[0007] The Hall sensor array includes N Hall sensors corresponding one-to-one with N buttons, and the controllable power supply array includes N controllable power supplies. Each Hall sensor has one power supply terminal, one output terminal, and one ground terminal. The power supply terminal of each Hall sensor is connected to the output terminal of the corresponding controllable power supply, and the ground terminal of the Hall sensor is grounded. Each controllable power supply has one output terminal, one high-voltage enable terminal, and one low-voltage enable terminal. The signals input to the high-voltage enable terminal and the low-voltage enable terminal are not simultaneously high-level. When the high-voltage enable terminal input is high-level, the output terminal of the controllable power supply outputs a high voltage. When the low-voltage enable terminal input is high-level, the output terminal of the controllable power supply outputs a low voltage. When both the high-voltage enable terminal and the low-voltage enable terminal input are low-level, the output terminal of the controllable power supply is blocked, i.e., no output is generated. The high-voltage enable terminals and low-voltage enable terminals of the N controllable power supplies are connected to a control module, and the control module controls the output of each controllable power supply.

[0008] The control module has a built-in motion threshold register and a trigger threshold register, which are used to store the motion threshold and the trigger threshold, respectively. The control module is connected to the communication bus, and the host computer configures the motion threshold register and the trigger threshold register through the communication bus and obtains the status of the corresponding button of the Hall sensor.

[0009] Each N-to-1 selector has N inputs, one output, and a set of selection terminals. The outputs of the N Hall sensors are connected to the corresponding inputs of two N-to-1 selectors. The output of the first N-to-1 selector is connected to one input of an analog comparator, the other input of the analog comparator is connected to the output of a digital-to-analog converter (DAC), and the input of the DAC is connected to the movement threshold register within the control module. The output of the second N-to-1 selector is connected to the input of an analog-to-digital converter (ADC), the output of the ADC is connected to one input of a digital comparator, and the other input of the digital comparator is connected to the trigger threshold register within the control module. The selection terminals of the two N-to-1 selectors are connected to the control module. The outputs of the analog comparator and the digital comparator are connected to the two input ports of the control module.

[0010] Another object of the present invention is to provide a readout method using the Hall sensor array readout circuit of the magnetic shaft keyboard.

[0011] The host computer configures the movement threshold and trigger threshold into the movement threshold register and trigger threshold register respectively via the communication bus. Both the movement threshold and trigger threshold are digital signals, and the trigger threshold includes a press threshold and a release threshold. The movement threshold is converted into an analog movement threshold level signal by a digital-to-analog converter (DAC) and continuously input into an analog comparator. The digital trigger threshold level signal is continuously input into a digital comparator. A low-speed scan list and a high-speed scan list are set. All Hall sensors in the low-speed scan list are scanned at a long interval T1, and all Hall sensors in the high-speed scan list are scanned at a short interval T2, where T1 > T2. During initialization, the numbers of N Hall sensors are placed in the low-speed scan list, and the high-speed scan list is empty.

[0012] The system continuously scans the status of each Hall sensor listed in the inventory at a low speed with a long interval T1. When no button is pressed, each Hall sensor is in controllable power supply P. j During the period when the low-voltage enable terminal is high, the corresponding output of the analog comparator is high, and each Hall sensor is in controllable power supply P. j When the low-voltage enable terminal is at a low level, the output of each controllable power supply is a high blocking circuit, and the Hall sensor does not consume power.

[0013] If a button is pressed, the magnet of that button approaches the corresponding Hall sensor. During the period when the low-voltage enable terminal of the controllable power supply is high, the Hall sensor outputs a voltage. The Hall sensor output voltage is compared with the analog movement threshold level signal, and the analog comparator outputs a signal. After the control module obtains the analog comparator output signal, when the condition is met, the number of the Hall sensor is removed from the low-speed scan list and placed in the high-speed scan list.

[0014] The system continuously scans the status of each Hall sensor in the list at short intervals (T2). The control module controls the corresponding controllable power supply output to either a high blocking circuit or a high level. The digital comparator compares the output of the analog-to-digital converter with the current trigger threshold.

[0015] Based on the output of the Hall sensor in the current cycle corresponding to the digital comparator, the control module reports the status of the button corresponding to the Hall sensor to the host computer via the communication bus, including pressed, released, and stationary. When the conditions are met, the number of the Hall sensor is removed from the high-speed scan list and placed in the low-speed scan list.

[0016] This invention utilizes the current and output characteristics of Hall sensors to perform adaptive frequency and voltage modulation, significantly reducing the operating current of the Hall sensor array while also improving the effective refresh rate of keyboard keys. This invention extends the operating time of magnetic axis keyboards, reduces key latency, and improves product performance. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the readout circuit for the Hall sensor array of the magnetic shaft keyboard of the present invention. Detailed Implementation

[0018] like Figure 1 As shown, the Hall sensor array readout circuit of the magnetic axis keyboard includes a Hall sensor array, a controllable power supply array, a control module U, two N-to-1 selectors, an analog comparator C1, a digital comparator C2, an analog-to-digital converter (ADC), and a digital-to-analog converter (DAC).

[0019] The Hall sensor array includes N Hall sensors H1, H2, ..., H1, each corresponding to one of the N buttons. N The controllable power supply array includes N controllable power supplies P1, P2, ..., P... N Each Hall sensor H has one power supply terminal, one output terminal, and one ground terminal. Each Hall sensor H1, H2, ..., H... N The power supply terminals are connected to the corresponding controllable power supplies P1, P2, ..., P. N The output terminal of the Hall sensor is grounded. Each controllable power supply P has one output terminal, one high-voltage enable terminal, and one low-voltage enable terminal. The signals input to the high-voltage enable terminal and the low-voltage enable terminal are not simultaneously high. When the high-voltage enable terminal input is high, the output terminal of the controllable power supply outputs a high voltage; when the low-voltage enable terminal input is high, the output terminal of the controllable power supply outputs a low voltage; when both the high-voltage enable terminal and the low-voltage enable terminal input are low, the output terminal of the controllable power supply is blocked, i.e., no output is output. The high-voltage enable terminals and low-voltage enable terminals of N controllable power supplies are connected to the control module U, and the control module U controls the output of each controllable power supply.

[0020] The control module U has built-in motion threshold register and trigger threshold register, which are used to store the motion threshold and trigger threshold, respectively. The control module U is connected to the communication bus. The host computer configures the motion threshold register and trigger threshold register through the communication bus and obtains the state of the corresponding button of the Hall sensor. The communication bus can be I2C or SPI, which is common knowledge in the industry.

[0021] Each N-to-1 selector has N inputs, one output, and a set of selection terminals. The outputs of the N Hall effect sensors are connected to the corresponding inputs of two N-to-1 selectors. The output of the first N-to-1 selector, MUX1, is connected to one input of analog comparator C1. The other input of analog comparator C1 is connected to the output of digital-to-analog converter (DAC). The input of DAC is connected to the shift threshold register within control module U. The output of the second N-to-1 selector, MUX2, is connected to the input of analog-to-digital converter (ADC). The output of ADC is connected to one input of digital comparator C2. The other input of digital comparator C2 is connected to the trigger threshold register within control module U. The selection terminals of the two N-to-1 selectors are connected to control module U. The outputs of analog comparator C1 and digital comparator C2 are connected to two input ports of control module U.

[0022] When a button magnet approaches a Hall sensor, the Hall sensor's output decreases or increases depending on the magnet's pole orientation. The magnet's orientation can be selected during installation without losing generality. For example, if a button approaches a Hall sensor, the output decreases. The Hall sensor array readout method is as follows:

[0023] Step (1) The host computer configures the movement threshold and trigger threshold to the movement threshold register and trigger threshold register respectively through the communication bus. Both the movement threshold and the trigger threshold are digital signals. The trigger threshold includes the press threshold and the release threshold. The movement threshold is converted into an analog movement threshold level signal by the digital-to-analog converter DAC and continuously input to the analog comparator C1. The digital trigger threshold level signal is continuously input to the digital comparator C2.

[0024] Step (2) Set up a low-speed scan list and a high-speed scan list; scan all Hall sensors in the low-speed scan list at a long interval T1, and scan all Hall sensors in the high-speed scan list at a short interval T2, where T1 > T2.

[0025] During initialization in step (3), N Hall sensors H1, H2, ..., H are set. N The number is placed in the low-speed scan list, and the high-speed scan list is empty.

[0026] Step (4) The control module U continuously scans each Hall sensor H in the list at a long interval T1. j Status: Will be connected to Hall sensor H j Connected controllable power supply P j The low-voltage enable pin is set to high level, and the controllable power supply P j Output low voltage; control the selection terminal of the first N-to-1 selector MUX1, so that the output terminal of the first N-to-1 selector MUX1 is connected to the Hall sensor H. j Connect, analog comparator C1 compares Hall sensor H j The output signal of the Hall sensor H is compared with the analog motion threshold level signal. j If the output signal is higher than the analog motion threshold level, analog comparator C1 outputs a high level; otherwise, it outputs a low level. After a delay of one switching time t1, control module U obtains the output of analog comparator C1 and compares it with the Hall sensor H. j Connected controllable power supply P j The low-voltage enable pin is set to low level, and the controllable power supply P j High blocking circuit at the output end;

[0027] When no button is pressed, each Hall sensor is powered by a controllable power supply P. j During the period when the low-voltage enable terminal is high, the corresponding output of analog comparator C1 is high, and each Hall sensor is in controllable power supply P. j When the low-voltage enable terminal is at a low level, the output of each controllable power supply is a high blocking circuit, and the Hall sensor does not consume power.

[0028] Step (5) If the i-th button is pressed down, the button magnet approaches the corresponding Hall sensor H. i Hall sensor H i Output voltage decreases, Hall sensor H i When the output voltage is lower than the analog movement threshold level signal, analog comparator C1 outputs a low level; control module U obtains the low-level signal output by analog comparator C1 and sets the Hall sensor H... i The number is removed from the low-speed scan list and placed in the high-speed scan list.

[0029] Step (6) Control module U continuously scans each Hall sensor H in the list with short intervals T2 and high speed. i Status: Will be connected to Hall sensor H i Connected controllable power supply P i The high-voltage enable terminal is set to high level, and the controllable power supply P i Output high voltage; control the selection terminal of the second N-to-1 selector MUX2, so that the output terminal of the second N-to-1 selector MUX2 is connected to the Hall sensor H.i Connect, the analog-to-digital converter (ADC) will connect the Hall sensor H i The output signal is converted into a digital signal. Digital comparator C2 compares the output of the analog-to-digital converter (ADC) with the current trigger threshold. If the ADC output is higher than the trigger threshold, digital comparator C2 outputs a high level; otherwise, it outputs a low level. After a delay of t2 (another switch delay), the control module U obtains the output of digital comparator C2 and compares it with the Hall sensor H. i Connected controllable power supply P i The high-voltage enable terminal is set to low level, and the controllable power supply P i High blocking circuit at the output end; t2 > t1.

[0030] Step (7) If the current period Hall sensor H i When the output of digital comparator C2 is low, while it was high in the previous cycle, control module U reports to the host computer via the communication bus that the Hall sensor H is low. i When the corresponding button is pressed, the host computer processes it accordingly; the control module U updates the trigger threshold to the release threshold.

[0031] If the Hall sensor H is in the current cycle i When the output of digital comparator C2 is high, and the previous cycle was low, the control module U reports to the host computer via the communication bus that the Hall sensor H is high. i When the corresponding button is released, the host computer processes it accordingly, and the control module U updates the trigger threshold to the pressed threshold; the Hall sensor H... n The number is removed from the high-speed scan list and placed in the low-speed scan list;

[0032] If the Hall sensor H is in the current cycle i The output of digital comparator C2 is the same as the output of the previous cycle, so no processing is performed.

[0033] Step (8) returns to step (4), and the control module U continues to scan the status of each Hall sensor numbered in the low-speed scan list and the high-speed scan list.

[0034] If a button is used to approach the Hall sensor, the Hall sensor output increases and the Hall sensor array readout method is the same as the decrease method, with steps (1) to (3) being the same.

[0035] Step (4) The control module U continuously scans each Hall sensor H in the list at a long interval T1. j Status: Will be connected to Hall sensor H j Connected controllable power supply P j The low-voltage enable pin is set to high level, and the controllable power supply P jOutput low voltage; control the selection terminal of the first N-to-1 selector MUX1, so that the output terminal of the first N-to-1 selector MUX1 is connected to the Hall sensor H. j Connect, analog comparator C1 compares Hall sensor H j The output signal of the Hall sensor H is compared with the analog motion threshold level signal. j If the output signal is higher than the analog motion threshold level signal, analog comparator C1 outputs a high level; otherwise, it outputs a low level. After a delay of one switching time t1, control module U obtains the output of analog comparator C1 and compares it with the Hall sensor H. j Connected controllable power supply P j The low-voltage enable pin is set to low level, and the controllable power supply P j High blocking circuit at the output end;

[0036] When no button is pressed, each Hall sensor is powered by a controllable power supply P. j During the period when the low-voltage enable terminal is high, the corresponding output of analog comparator C1 is high, and each Hall sensor is in controllable power supply P. j When the low-voltage enable terminal is at a low level, the output of each controllable power supply is a high blocking circuit, and the Hall sensor does not consume power.

[0037] Step (5) If the i-th button is pressed down, the button magnet approaches the corresponding Hall sensor H. i Hall sensor H i As the output voltage increases, the Hall sensor H... i When the output voltage of the sensor is higher than the analog motion threshold level signal, the analog comparator C1 outputs a high level; the control module U acquires the high-level signal output by the analog comparator C1 and activates the Hall sensor H. i The number is removed from the low-speed scan list and placed in the high-speed scan list.

[0038] Step (6) Control module U continuously scans each Hall sensor H in the list with short intervals T2 and high speed. i Status: Will be connected to Hall sensor H i Connected controllable power supply P i The high-voltage enable terminal is set to high level, and the controllable power supply P i Output high voltage; control the selection terminal of the second N-to-1 selector MUX2, so that the output terminal of the second N-to-1 selector MUX2 is connected to the Hall sensor H. i Connect, the analog-to-digital converter (ADC) will connect the Hall sensor H iThe output signal is converted into a digital signal. Digital comparator C2 compares the ADC output with the current trigger threshold. If the ADC output is lower than the trigger threshold, digital comparator C2 outputs a low level; otherwise, it outputs a high level. After a delay of t2 (another switch delay), the control module U obtains the output of digital comparator C2 and compares it with the Hall sensor H. i Connected controllable power supply P i The high-voltage enable terminal is set to low level, and the controllable power supply P i High blocking circuit at the output end; t2 > t1.

[0039] Step (7) If the current period Hall sensor H i When the output of digital comparator C2 is high, and the previous cycle was low, the control module U reports to the host computer via the communication bus that the Hall sensor H is high. i When the corresponding button is pressed, the host computer processes it accordingly; the control module U updates the trigger threshold to the release threshold.

[0040] If the Hall sensor H is in the current cycle i When the output of digital comparator C2 is low, while it was high in the previous cycle, control module U reports to the host computer via the communication bus that the Hall sensor H is low. i When the corresponding button is released, the host computer processes it accordingly, and the control module U updates the trigger threshold to the pressed threshold; the Hall sensor H... i The number is removed from the high-speed scan list and placed in the low-speed scan list;

[0041] If the Hall sensor H is in the current cycle i The output of digital comparator C2 is the same as the output of the previous cycle, so no processing is performed.

[0042] Step (8) returns to step (4), and the control module U continues to scan the status of each Hall sensor numbered in the low-speed scan list and the high-speed scan list.

[0043] When configuring the movement threshold via the communication bus, the host computer can use any of the following methods:

[0044] 1. A motion threshold register stores a motion threshold, which is used by N Hall sensors.

[0045] 2. For N Hall sensors, the movement threshold register stores N movement thresholds, and each Hall sensor uses its own movement threshold; all N movement thresholds are different, or some are the same.

[0046] When configuring the trigger threshold via the communication bus, the host computer can use any of the following methods:

[0047] 1. The trigger threshold register stores a set of trigger thresholds, which are used by N Hall sensors.

[0048] 2. For N Hall sensors, the trigger threshold register stores N sets of trigger thresholds, and each Hall sensor uses its own trigger threshold; all N sets of trigger thresholds are different, or some are the same.

[0049] The release threshold can be either a fixed release threshold or a fallback release threshold, which the user can choose according to their own habits by configuring the trigger threshold on the host computer. If a fixed release threshold is selected, the release threshold remains unchanged during operation. If a fallback release threshold is selected, the release threshold used during operation is the updated fallback release threshold: The host computer first configures the fixed release threshold through the communication bus; if the Hall sensor is approached by a button, the output of the Hall sensor decreases, and the control module U calculates the minimum value of the ADC output corresponding to each Hall sensor within a set time t3 before the current moment. The sum of this minimum value and the fixed release threshold is the current fallback release threshold; if the Hall sensor is approached by a button, the output of the Hall sensor increases, and the control module U calculates the maximum value of the ADC output corresponding to each Hall sensor within a set time t3 before the current moment. The difference between this maximum value and the fixed release threshold is the current fallback release threshold; 1ms ≤ t3 ≤ 30ms, and in this embodiment, t3 = 5ms is used.

Claims

1. A readout circuit for a Hall sensor array on a magnetic shaft keyboard, characterized in that: It includes a Hall sensor array, a controllable power supply array, a control module, two N-to-1 selectors, an analog comparator, a digital comparator, an analog-to-digital converter, and a digital-to-analog converter; The Hall sensor array includes N Hall sensors, each corresponding to one of the N buttons. The controllable power supply array includes N controllable power supplies. Each Hall sensor has one power supply terminal, one output terminal, and one ground terminal. The power supply terminal of each Hall sensor is connected to the output terminal of the corresponding controllable power supply, and the ground terminal of the Hall sensor is grounded. Each controllable power supply has one output terminal, one high-voltage enable terminal, and one low-voltage enable terminal. The signals input to the high-voltage enable terminal and the low-voltage enable terminal are not simultaneously high-level. When the high-voltage enable terminal input is high-level, the output terminal of the controllable power supply outputs a high voltage. When the low-voltage enable terminal input is high-level, the output terminal of the controllable power supply outputs a low voltage. When both the high-voltage enable terminal and the low-voltage enable terminal input are low-level, the output terminal of the controllable power supply is blocked, i.e., no output is generated. The high-voltage enable terminals and low-voltage enable terminals of the N controllable power supplies are connected to a control module, and the control module controls the output of each controllable power supply. The control module has a built-in motion threshold register and trigger threshold register, which are used to store the motion threshold and trigger threshold respectively; the control module is connected to the communication bus, and the host computer configures the motion threshold register and trigger threshold register through the communication bus and obtains the state of the corresponding button of the Hall sensor; Each N-to-1 selector has N inputs, one output, and a set of selection terminals. The outputs of the N Hall sensors are connected to the corresponding inputs of two N-to-1 selectors. The output of the first N-to-1 selector is connected to one input of an analog comparator, the other input of the analog comparator is connected to the output of a digital-to-analog converter (DAC), and the input of the DAC is connected to the movement threshold register within the control module. The output of the second N-to-1 selector is connected to the input of an analog-to-digital converter (ADC), the output of the ADC is connected to one input of a digital comparator, and the other input of the digital comparator is connected to the trigger threshold register within the control module. The selection terminals of the two N-to-1 selectors are connected to the control module. The outputs of the analog comparator and the digital comparator are connected to the two input ports of the control module.

2. The readout method using the Hall sensor array readout circuit of the magnetic axis keyboard as described in claim 1, characterized in that: The host computer configures the movement threshold and trigger threshold to the movement threshold register and trigger threshold register respectively through the communication bus. The movement threshold and trigger threshold are both digital signals. The trigger threshold includes the press threshold and the release threshold. The motion threshold is converted into an analog motion threshold level signal by a digital-to-analog converter (DAC) and continuously input to the analog comparator. A digital trigger threshold level signal is continuously input to a digital comparator; a low-speed scan list and a high-speed scan list are set; all Hall sensors in the low-speed scan list are scanned at a long interval T1, and all Hall sensors in the high-speed scan list are scanned at a short interval T2, where T1 > T2; during initialization, the numbers of N Hall sensors are placed in the low-speed scan list, and the high-speed scan list is empty. The system continuously scans the status of each Hall sensor listed in the inventory at a low speed with a long interval T1. When no button is pressed, each Hall sensor is in controllable power supply P. j During the period when the low-voltage enable terminal is high, the corresponding output of the analog comparator is high, and each Hall sensor is in controllable power supply P. j When the low-voltage enable terminal is at a low level, the output of each controllable power supply is a high blocking circuit, and the Hall sensor does not consume power. If a button is pressed, the magnet of that button approaches the corresponding Hall sensor. During the period when the low-voltage enable terminal of the controllable power supply is high, the Hall sensor outputs a voltage. The Hall sensor output voltage is compared with the analog movement threshold level signal, and the analog comparator outputs a signal. After the control module obtains the analog comparator output signal, when the condition is met, the number of the Hall sensor is removed from the low-speed scan list and placed in the high-speed scan list. The system continuously scans the status of each Hall sensor in the list at short intervals (T2). The control module controls the corresponding controllable power supply output to either a high blocking circuit or a high level. The digital comparator compares the output of the analog-to-digital converter with the current trigger threshold. Based on the output of the Hall sensor in the current cycle corresponding to the digital comparator, the control module reports the status of the button corresponding to the Hall sensor to the host computer via the communication bus, including pressed, released, and stationary. When the conditions are met, the number of the Hall sensor is removed from the high-speed scan list and placed in the low-speed scan list.

3. The method for reading out a Hall sensor array from a magnetic axis keyboard as described in claim 2, characterized in that, The Hall sensor array readout method is as follows: When a button is placed near the Hall sensor, the output of the Hall sensor decreases. Step (1) The host computer configures the movement threshold and trigger threshold into the movement threshold register and trigger threshold register respectively through the communication bus. The movement threshold is converted into an analog movement threshold level signal by the digital-to-analog converter and continuously input into the analog comparator. A digital trigger threshold level signal is continuously input to the digital comparator; Step (2) Set up a low-speed scan list and a high-speed scan list; scan all Hall sensors in the low-speed scan list at a long interval T1, and scan all Hall sensors in the high-speed scan list at a short interval T2, where T1 > T2. During initialization in step (3), the numbers of the N Hall sensors are placed in the low-speed scan list, and the high-speed scan list is empty; Step (4) The control module continuously scans each Hall sensor H in the list at a long interval T1 and at a low speed. j Status: Will be connected to Hall sensor H j Connected controllable power supply P j The low-voltage enable pin is set to high level, and the controllable power supply P j Output low voltage; control the selection terminal of the first N-to-1 selector, so that the output terminal of the first N-to-1 selector is connected to the Hall sensor H. j Connect, analog comparator compares Hall sensor H j The output signal of the Hall sensor H is compared with the analog motion threshold level signal. j If the output signal is higher than the analog motion threshold level, the analog comparator outputs a high level; otherwise, it outputs a low level. After a delay of one switching time t1, the control module obtains the output of the analog comparator and compares it with the Hall sensor H. j Connected controllable power supply P j The low-voltage enable pin is set to low level, and the controllable power supply P j High blocking circuit at the output end; When no button is pressed, each Hall sensor is powered by a controllable power supply P. j During the period when the low-voltage enable terminal is high, the corresponding output of analog comparator C1 is high, and each Hall sensor is in controllable power supply P. j When the low-voltage enable terminal is at a low level, the output of each controllable power supply is a high blocking circuit, and the Hall sensor does not consume power. Step (5) If the i-th button is pressed down, the button magnet approaches the corresponding Hall sensor H. i Hall sensor H i When the output voltage decreases and the output voltage of the Hall sensor Hi falls below the analog motion threshold level signal, the analog comparator outputs a low level. The control module acquires the low-level signal output by the analog comparator and sets the Hall sensor H... i The number is removed from the low-speed scan list and placed in the high-speed scan list; Step (6) The control module continuously scans each Hall sensor H in the list at short intervals T2 using a high-speed scan. i Status: Will be connected to Hall sensor H i Connected controllable power supply P i The high-voltage enable terminal is set to high level, and the controllable power supply P i Output high voltage; control the selection terminal of the second N-to-1 selector, so that the output terminal of the second N-to-1 selector is connected to the Hall sensor H. i Connect, the analog-to-digital converter will connect the Hall sensor H i The output signal is converted into a digital signal. The digital comparator compares the analog-to-digital converter output with the current trigger threshold. If the analog-to-digital converter output is higher than the trigger threshold, the digital comparator outputs a high level; otherwise, it outputs a low level. After a delay of t2 from another switch, the control module obtains the output of the digital comparator and compares it with the Hall sensor H. i Connected controllable power supply P i The high-voltage enable terminal is set to low level, and the controllable power supply P i High blocking circuit at the output end; t2 > t1; Step (7) If the current period Hall sensor H i When the output of the digital comparator is low and the previous cycle was high, the control module reports to the host computer via the communication bus that the button corresponding to the Hall sensor Hi has been pressed, and the host computer processes the request accordingly; the control module updates the trigger threshold to the release threshold. If the Hall sensor H is in the current cycle i When the output of the digital comparator is high, and the previous cycle was low, the control module reports to the host computer via the communication bus that the Hall sensor H... i When the corresponding button is released, the host computer processes it accordingly, and the control module updates the trigger threshold to the pressed threshold; the Hall sensor H... i The number is removed from the high-speed scan list and placed in the low-speed scan list; If the output of the Hall sensor Hi in the current cycle is the same as the output of the previous cycle, no processing is performed. Step (8) returns to step (4), and the control module continues to scan the status of each Hall sensor numbered in the low-speed scan list and the high-speed scan list.

4. The method for reading out a Hall sensor array from a magnetic axis keyboard as described in claim 2, characterized in that, The Hall sensor array readout method is as follows: The Hall sensor output increases when a button is pressed near the Hall sensor. Step (1) The host computer configures the movement threshold and trigger threshold into the movement threshold register and trigger threshold register respectively through the communication bus. The movement threshold is converted into an analog movement threshold level signal by the digital-to-analog converter and continuously input into the analog comparator. A digital trigger threshold level signal is continuously input to the digital comparator; Step (2) Set up a low-speed scan list and a high-speed scan list; scan all Hall sensors in the low-speed scan list at a long interval T1, and scan all Hall sensors in the high-speed scan list at a short interval T2, where T1 > T2. During initialization in step (3), the numbers of the N Hall sensors are placed in the low-speed scan list, and the high-speed scan list is empty; Step (4) The control module continuously scans each Hall sensor H in the list at a long interval T1 and at a low speed. j Status: Will be connected to Hall sensor H j Connected controllable power supply P j The low-voltage enable pin is set to high level, and the controllable power supply P j Output low voltage; control the selection terminal of the first N-to-1 selector, so that the output terminal of the first N-to-1 selector is connected to the Hall sensor H. j Connect, analog comparator compares Hall sensor H j The output signal of the Hall sensor H is compared with the analog motion threshold level signal. j If the output signal is higher than the analog motion threshold level, the analog comparator outputs a high level; otherwise, it outputs a low level. After a delay of one switching time t1, the control module obtains the output of the analog comparator and compares it with the Hall sensor H. j Connected controllable power supply P j The low-voltage enable pin is set to low level, and the controllable power supply P j High blocking circuit at the output end; When no button is pressed, each Hall sensor is powered by a controllable power supply P. j During the period when the low-voltage enable terminal is high, the corresponding output of analog comparator C1 is high, and each Hall sensor is in controllable power supply P. j When the low-voltage enable terminal is at a low level, the output of each controllable power supply is a high blocking circuit, and the Hall sensor does not consume power. Step (5) If the i-th button is pressed down, the button magnet approaches the corresponding Hall sensor H. i The Hall sensor Hi output voltage increases, Hall sensor H i When the output voltage of the analog comparator is higher than the analog motion threshold level signal, the analog comparator outputs a high level; the control module acquires the high-level signal output by the analog comparator and sets the Hall sensor H... i The number is removed from the low-speed scan list and placed in the high-speed scan list; Step (6) The control module continuously scans each Hall sensor H in the list at short intervals T2 using a high-speed scan. i Status: Will be connected to Hall sensor H i Connected controllable power supply P i The high-voltage enable terminal is set to high level, and the controllable power supply P i Output high voltage; control the selection terminal of the second N-to-1 selector, so that the output terminal of the second N-to-1 selector is connected to the Hall sensor H. i Connect, the analog-to-digital converter will connect the Hall sensor H i The output signal is converted into a digital signal. The digital comparator compares the analog-to-digital converter output with the current trigger threshold. If the analog-to-digital converter output is lower than the trigger threshold, the digital comparator outputs a low level; otherwise, it outputs a high level. After a delay of t2 (another switch delay), the control module obtains the output of the digital comparator and compares it with the Hall sensor H. i The high-voltage enable pin of the connected controllable power supply Pi is set to low level, and the controllable power supply P... i High blocking circuit at the output; t2 > t1; Step (7) If the current period Hall sensor H i When the output of the digital comparator is high, and the previous cycle was low, the control module reports to the host computer via the communication bus that the Hall sensor H... i When the corresponding button is pressed, the host computer processes it accordingly; the control module updates the trigger threshold to the release threshold. If the Hall sensor H is in the current cycle i When the output of the digital comparator is low, while it was high in the previous cycle, the control module reports to the host computer via the communication bus that the Hall sensor H... i When the corresponding button is released, the host computer processes it accordingly, and the control module updates the trigger threshold to the pressed threshold; the number of Hall sensor Hi is removed from the high-speed scan list and placed in the low-speed scan list; If the Hall sensor H is in the current cycle i If the output of the digital comparator is the same as the output of the previous cycle, no processing is performed. Step (8) returns to step (4), and the control module continues to scan the status of each Hall sensor numbered in the low-speed scan list and the high-speed scan list.

5. The method for reading out a Hall sensor array from a magnetic axis keyboard as described in claim 3 or 4, characterized in that, When configuring the movement threshold via the communication bus, the host computer can use any of the following methods: The motion threshold register stores a motion threshold, which is used by N Hall sensors; or For N Hall sensors, the motion threshold register stores N motion thresholds, and each Hall sensor uses its own motion threshold. All N moving thresholds are different, or some are the same.

6. The method for reading out a Hall sensor array from a magnetic axis keyboard as described in claim 3 or 4, characterized in that, When configuring the trigger threshold via the communication bus, the host computer can use any of the following methods: The trigger threshold register stores a set of trigger thresholds, which are used by N Hall sensors; or For N Hall sensors, the trigger threshold register stores N sets of trigger thresholds, and each Hall sensor uses its own trigger threshold. All N trigger thresholds are different, or some are the same.

7. The method for reading out a Hall sensor array from a magnetic axis keyboard as described in claim 3 or 4, characterized in that: The release threshold can be a fixed release threshold or a fallback release threshold. Users can choose the trigger threshold themselves by configuring it on the host computer according to their own habits. If a fixed release threshold is selected, the release threshold will remain unchanged during operation; If a rollback release threshold is selected, the updated rollback release threshold will be used during operation: The host computer first configures the fixed release threshold through the communication bus; if the button is used to approach the Hall sensor and the Hall sensor output decreases, the control module calculates the minimum value of the analog-to-digital converter output corresponding to each Hall sensor within a set time t3 before the current moment, and the sum of this minimum value and the fixed release threshold is the current rollback release threshold; if the button is used to approach the Hall sensor and the Hall sensor output increases, the control module calculates the maximum value of the analog-to-digital converter output corresponding to each Hall sensor within a set time t3 before the current moment, and the difference between this maximum value and the fixed release threshold is the current rollback release threshold.

8. The method for reading out a Hall sensor array from a magnetic axis keyboard as described in claim 7, characterized in that: 1mS≤t3≤30mS.

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