1、 Serial port connection method
Serial port connection refers to controlling the sound of the buzzer by outputting high and low levels through the serial port. The positive pole of the buzzer needs to be connected to the output pin of the microcontroller, and the negative pole needs to be connected to the GND. By controlling the high and low levels of the output pins, the buzzer can be controlled to sound and stop. This connection method is suitable for small buzzers controlled by microcontrollers.
2、 Parallel port connection method
Parallel port connection refers to controlling the sound of the buzzer through parallel port output data. Generally, communication only requires the use of 8 data lines and 1 control line. The advantage of this method is its fast speed, but it requires connecting multiple lines and is more complex. It is necessary to connect the positive and negative poles of the buzzer to the data line output by the parallel port, and at the same time, connect the control line to the control pin.
3、Different types of buzzer wiring methods
- Active buzzer
The active buzzer has an oscillator inside, which can emit sound by simply connecting it to the power supply. It will generate the required frequency signal internally, so there is no need to control the circuit. It can be directly connected to the power supply to make it emit sound.
- Passive buzzer
Passive buzzers require an external circuit to function. An oscillator needs to be connected during use to produce sound. It should be noted that the passive buzzer cannot be directly connected to the IO port of the microcontroller. It needs to be controlled by cascading a transistor in the middle to achieve stable and normal working conditions.
4、 Frequently Asked Questions
- No sound from buzzer: Check if the wiring is correct, if the output pins of the microcontroller are configured in output mode, and if the working voltage of the buzzer matches
- The sound of the buzzer is too low: it may be because the driving circuit is too simple, and an appropriate amplification circuit needs to be added.
- How to control the specific frequency and duration of the buzzer: It is necessary to write corresponding programs to control the high and low levels of the output pins of the microcontroller to achieve control of the frequency and duration of the buzzer’s sound.