BakeBit - Button/zh

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1 介绍

按键
  • BakeBit - Button是一个瞬时(非自锁)按钮开关模块,用于检测按键事件,按钮被释放后自动恢复到常态。
  • 在按钮未被按下时模块输出高电平,按钮被按下后输出低电平。

2 特性

  • 使用标准的2.0mm 4 Pin BakeBit接口
  • 数字信号输出
  • PCB尺寸(mm):20x24

BakeBit - Button.PCB

  • 引脚说明:
名称 描述
GND
5V 电源5V
NC
SIG 信号

3 示例程序:Button And Buzzer

本示例需要配合蜂鸣器使用。

3.1 硬件连接

简单的将 蜂鸣器 模块插入 D3接口,将 按键 插入 D4 接口,如下面这样:

Button And Buzzer-1.jpg Button And Buzzer-2.jpg

3.2 示例源代码

import time
from bakebit import *
import math
 
buzzer_pin = 3		#Port for buzzer
button = 4		#Port for Button
old_button_status = -1
pinMode(buzzer_pin,"OUTPUT")	# Assign mode for buzzer as output
pinMode(button,"INPUT")		# Assign mode for Button as input
 
buzzer_on = False
old_buzzer_on = not buzzer_on
button_pressed = False
 
while True:
	try:
		while True:
			button_status = digitalRead(button)	#Read the Button status
			# print button_status
			if old_button_status < 0: 
				break
 
			if button_status != old_button_status:
				break
 
		time.sleep(0.2)
		old_button_status = button_status
 
		if button_status == 0:
			button_pressed = True
		else:
			if button_pressed:
				buzzer_on = not buzzer_on
			button_pressed = False 
 
		if old_buzzer_on != buzzer_on:
			old_buzzer_on = buzzer_on
			if buzzer_on:
				analogWrite(buzzer_pin,127)
				print "Buzzing"
			else:
				analogWrite(buzzer_pin,0)
				print "\tOff"			
 
		time.sleep(0.2)			
	except KeyboardInterrupt:	# Stop the buzzer before stopping
		digitalWrite(buzzer_pin,0)
		break
	except (IOError,TypeError) as e:
		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_prj_Button_And_Buzzer.py:

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

3.4 运行结果

当点击按键时,蜂鸣器会响起,再次点击按键,蜂鸣器停止。

4 相关资料