BakeBit - Sound Sensor/zh

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English

1 介绍

Sound Sensor
  • BakeBit - Sound Sensor是一个声音检测模块,用于检测声音信号。模块使用了一个内置对声音敏感的电容式驻极体话筒检测声波信号,声波使话筒内的驻极体薄膜振动,导致电容的变化,而产生与之对应变化的微小电压,经过LM358放大后输出。
  • 在默认状态下模块输出高电平,当检测到有声音的时候输出低电平,声音消失后恢复高电平,没有延时。

2 特性

  • 使用标准的2.0mm 4 Pin BakeBit接口

BakeBit - Sound Sensor

  • 引脚说明:
名称 描述
GND
5V 电源5V
NC
SIG 信号

3 示例程序:Sound Sensor

这个示例用Sound Sensor实现一个声控开关,当检测到环境声音达到指定的分贝时,点亮LED。

3.1 硬件连接

简单的将 Sound Sensor 模块插入 A0 接口,将 LED 插入 D5 接口,如下面这样:

Sound Sensor-1.jpg Sound Sensor-2.jpg

3.2 示例源代码

import time
import bakebit
 
# Connect the BakeBit Sound Sensor to analog port A0
# SIG,NC,VCC,GND
sound_sensor = 0
 
# Connect the BakeBit LED to digital port D5
# SIG,NC,VCC,GND
led = 5
 
bakebit.pinMode(sound_sensor,"INPUT")
bakebit.pinMode(led,"OUTPUT")
 
# The threshold to turn the led on 400.00 * 5 / 1024 = 1.95v
threshold_value = 400
 
while True:
    try:
        # Read the sound level
        sensor_value = bakebit.analogRead(sound_sensor)
 
        # If loud, illuminate LED, otherwise dim
        if sensor_value > threshold_value:
            bakebit.digitalWrite(led,1)
        else:
            bakebit.digitalWrite(led,0)
 
        print("sensor_value = %d" %sensor_value)
        time.sleep(.2)
 
    except IOError:
        print ("Error")

Github


3.3 运行示例

假设你已经参考bakebit教程安装了BakeBit源代码,
要运行示例程序,可以在开发板上进入 BakeBit/Software/Python目录,运行bakebit_sound_sensor.py:

cd ~/BakeBit/Software/Python
sudo python bakebit_sound_sensor.py

3.4 运行结果

对着声音传感器制造点声音,例如拍打手掌,LED将被亮起。

4 相关资料