Keyboard of mobile terminal and method for realizing keying and keyboard lock for same

Abstract

The invention discloses a keyboard of a mobile terminal. The keyboard comprises a keyboard module and a keying processing module, wherein the keyboard module comprises normal keys, a lock key and a plurality of resistive dividers; the keying processing module comprises an analog / digital converter, and the analog / digital converter comprises an input port; the reference voltage ADC-REF of the analog / digital converter is connected to the input port via a resistor; the input port of the analog / digital converter is connected with a plurality of serially connected resistive dividers, and each resistive divider connects a normal key in series to ground; the input port of the analog / digital converter further connects one resistive divider and the lock key to ground; the keying processing module further comprises a control logic unit; and the control logic unit judges whether the keyboard is locked and judges the pressed key as the normal key or the lock key according to changes of an input voltage signal ADC-IN of the analog / digital converter. With the keyboard and the method disclosed by the invention, input / output port resource is saved, system resource of programs is saved, and simultaneously, complexity is reduced.

Description

technical field [0001] The invention relates to a keyboard and a keyboard locking method, in particular to a keyboard of a mobile terminal and a method for realizing key and keyboard locking. Background technique [0002] In the prior art, the following three methods are often used to realize common button and lock button methods, one is to collect signals through an analog-to-digital converter (Analog-to-Digital Converter is called for short ADC), if a zero value is detected as a lock, See figure 1 Among them, although the above method is simple and does not require additional input / output port (input / output, referred to as I / O) resources, there is a problem that if the lock key is pressed and other common keys are pressed, the analog / digital converter ( The input of the ADC) has been connected to the ground, the analog / digital converter (ADC) cannot detect other levels, the analog / digital converter (ADC) will not respond, so it cannot be judged that the keyboard has been ...

AI Technical Summary

Problems solved by technology

[0002] In the prior art, the following three methods are often used to realize common button and lock button methods, one is to collect signals through an analog-to-digital converter (Analog-to-Digital Converter is called for short ADC), if a zero value is detected as a lock, See figure 1 Among them, although the above method is simple and does not require additional input / output port (input / output, referred to as I / O) resources, there is a problem that if the lock key is pressed and other common keys are pressed, the analog / digital converter ( The input of the ADC) has been connected to the ground, the analog / digital converter (ADC) cannot detect other levels, the analog / digital converter (ADC) will not respond, so it cannot be judged that the keyboard has been locked. In the application, the user There is no way to know that it has been locked; the other is to realize multiple common keys through an analog / digital converter (ADC), and the locking key is realized through an input and output port (I / O), see figure 2 Among them, the above-mentioned method needs additional input and output port (I / O) mouth, especially in embedded system, input and output port (I / O) resource is particularly precious, and adding an input and output port (I / O) will have a negative effect on The entire system design adds a lot of cost. At the same time, in the application, the software also needs to control the input and output ports (I / O), which will be troublesome and increase the consumption of system resources; another method is to use the input and output ports ( I / O) scanning, the matrix mode realizes multiple common key functions, and the locking key is also realized through an input and output port (I / O), see image 3 , not only the lock key in method 1 needs additional input and output ports (I / O) to realize, but matrix scanning needs to occupy more input and output port (I / O) resources

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