基于单片机的I/O口实现的电容触摸感应技术,节省了触摸专业芯片资源,可以在任何MCU上实现,灵活性好,开发成本较低,易于实现。利用人体的对地电容,改变了电容的介电常数,对RC网络施加周期性的充电电压,通过A/D检测电容两端的电压,利用手触摸时电压的微小变化来判断是否有“按下”动作的产生,且利用这一变化的电压值可实现应用于音响音量调节的触摸滑动条的音量分级。 The capacitive touch sensing technology based on the I / O port of the microcontroller saves the resources of touch professional chips and can be implemented on any MCU with good flexibility, low development cost and easy implementation. Use of human body to ground capacitance, changing the dielectric constant of the capacitor, the RC network to apply periodic charging voltage, through the A / D detection voltage across the capacitor, the touch of small changes in voltage when used to determine whether there is Next "action, and using this changing voltage value allows the volume grading of the touch slider applied to the audio volume adjustment.