晶振是STC89C51单片机系统中不可或缺的元件，就晶振供给的时钟频率

The crystal oscillator is an indispensable element in the STC89C51 microcontroller system. In terms of the clock frequency supplied by the crystal oscillator, the lower the clock frequency, the slower the operating speed of the microcontroller system. The existence of the crystal oscillator mainly provides the clock signal for the single-chip system. As for the clock signal of the STC89C51 microcontroller, it includes two modes of internal clock and external clock, as shown in Figure 3-3 below is a block diagram of the internal clock structure of the STC89C51 microcontroller. On the basis of the oscillation circuit existing in the single-chip system, the crystal is connected to the 18 and 19 pins of the single-chip computer, and then two capacitors are connected in parallel to form a self-excited oscillator. signal. The main function of the two capacitors is to stabilize the frequency and speed up the oscillation. The capacitance value is between 5pF and 30pF, the most commonly used capacitance value is 30pF, the oscillation frequency value is between 1.2Mhz and 12Mhz, the most commonly used is 6Mhz and 12Mhz.

Crystal is an indispensable component in STC89C51 microcontroller system, the lower the clock frequency, the slower the speed of the microcontroller system, the higher the clock frequency, the faster the microcontroller system. The existence of crystal is mainly to provide clock signal for the microcontroller system. For the clock signal of the STC89C51 microcontroller, it includes two modes: internal clock and external clock, as shown in Figure 3-3 below, the frame of the internal clock structure of the STC89C51 microcontroller. On the basis of the oscillation circuit existing in the microcontroller system itself, the crystal is connected with the 18 and 19 pins of the microcontroller, and then two capacitors are connected in parallel to form the self-exciting oscillator, at which point the clock signal required by the microcontroller can be generated. The main functions of the two capacitors are to stabilize the frequency and speed up the oscillation. The size of the capacitor value is between 5pF and 30pF, the most commonly used capacitor value is 30pF, the oscillation frequency is between 1.2Mhz and 12Mhz, the most commonly used is 6Mhz and 12Mhz.

Crystal oscillator is an indispensable component in STC89C51 single-chip microcomputer system. In terms of the clock frequency supplied by crystal oscillator, the lower the clock frequency is, the slower the single-chip microcomputer system will run. The higher the clock frequency is, the faster the single-chip microcomputer system will run. Crystal oscillator is mainly used to provide clock signal for MCU system. For the clock signal of STC89C51, it includes two modes: internal clock and external clock, as shown in Figure 3-3 below is the internal clock structure diagram of STC89C51. On the basis of the oscillation circuit of the single chip microcomputer system, a self-excited oscillator is formed by connecting the crystal oscillator with the 18 and 19 pins of the single chip microcomputer, and then connecting two capacitors in parallel. At this time, the clock signal required by the single chip microcomputer can be generated. The main functions of the two capacitors are to stabilize the frequency and speed up the oscillation. The value of capacitance is between 5pf and 30pf, the most commonly used value is 30pf, the value of oscillation frequency is between 1.2MHz and 12Mhz, and the most commonly used values are 6mhz and 12Mhz.<br>