查看“光电门传感器”的源代码


[[文件:photo_gate.png.png|400px|缩略图|右 |blue:bit-光电门传感器]]<br />

== 概述 ==

Photogate Time是测量触发时刻和触发结束时刻的时间模块。

== 技术参数 ==
* 工作电压：VCC 3.3-5V
* I2C数字信号输出
* 时间范围 : 0～
* 解析度: 10微秒
* 精度: 2%
* 模块尺寸：24x46x7.5mm

== 引脚定义/接口说明 ==
{| class="wikitable"
|-
| <small>VCC</small> || <small>电源</small>
|-
| <small>SDA</small> || <small>I2C数据</small>
|-
| <small>SCL</small> || <small>I2C时钟</small>
|-
| <small>GND</small> || <small>地</small>
|}

{|style="background-color:#FCF8E3;color:#8A6D3B;"
|style="padding: 2px;"| 
* 拨动开关,可选择模块的I2C地址,用于避免与其他I2C设备地址冲突。注意,重新选择I2C地址后,需要重新上电才能生效！
|}

* 触发信号的输入接口

{| class="wikitable"
|-
| <small>VCC</small> || <small>电源</small>
|-
| <small>CH0</small> || <small>NA(未用)</small>
|-
| <small>CH1</small> || <small>触发信号输入</small>
|-
| <small>GND</small> || <small>地</small>
|}

* 可调电位器:调节触发信号的触发电平

== 使用教程 ==

* 在程序编程中需要注意拨动开关地址和程序中的地址一致!
* 计算信号的正脉宽时间,当输入信号由低变高为触发开始点,由高变低位触发触发结束点,计算之间的时间差。

=== <font size=3px>Arduino</font>  ===

<syntaxhighlight lang="Python" line='line'>

include <Wire.h>
int reading = 0;
int reading0 = 0;
int reading1 = 0;
int reading2 = 0;
int reading3 = 0;
int reading4 = 0;
long trigger_begin;
long trigger_end; 
float  trigger_time;
void Get_Photogate_value(char address)  
{
  Wire.requestFrom(0x51, 5); 
  if (5 <= Wire.available())
  {
       reading0 = Wire.read();
       reading1 = Wire.read();
       reading2 = Wire.read();
       reading3 = Wire.read();
       reading4 = Wire.read();
       if(reading0==1)
       {
         trigger_begin = reading1*16777216  + reading2*65536 + reading3*256 + reading4;
         //Serial.println(1);
         //Serial.println(trigger_begin);
       } 
       if(reading0==0)
       {
         trigger_end = reading1*16777216  + reading2*65536 + reading3*256 + reading4;
         //Serial.println(0);
         //Serial.println(trigger_end);
         trigger_time = (float)(trigger_end - trigger_begin)/2041667;     //250000    2041667
         Serial.println(trigger_time);         
       }
  
}
void setup()
{
  Wire.begin();        // join i2c bus (address optional for master)
  Serial.begin(9600);  // start serial for output
}

void loop()
{
  Get_Photogate_value(0x51);
}

</syntaxhighlight>

=== <font size=3px>掌控板</font> ===

* GitHub:[https://github.com/labplus-cn/mPython_bluebit bluebit for mPython library]
* bluebit for mPython library API: https://mpython-lib.readthedocs.io/zh/master/bluebit/index.html

<syntaxhighlight lang="Python" line='line'>

from mpython import *
import bluebit

a = bluebit.DelveBit(0x50)

while True:
    print(a.photo_gate())


</syntaxhighlight>

=== <font size=3px>microbit</font> ===

== 应用案例 ==

== FAQ ==

== 版本历史记录 ==

{|  border="1" cellspacing="0" align="left" cellpadding="0" width="60%" style="text-align:center;"
|- style="text-align:center;background-color:#6fa8dc;color:#fffff;" 
!width="10%"|Version !!width="15%"| Date !!  <small>新增/删除/修复</small>
|-
|  ||  || style="text-align:left"|

|}