arduino kitchen timer

This is what I want to use as a display under sun shine.

 https://github.com/MakersFunDuck/Common-Kitchen-Timer-With-LCD-Replacement-Board






I found this kind of display on Taobau, there are few common contact, just like the segment LED idsplay.
This vender provide me some info: 

奇耘电子



Even with frequent questions

 

1、液晶屏有反射模式、半透模式，还有全透模式，不知道有什么区别，该如何选择？

      反射模式：下偏光片不透明，所以不能接背光使用，适用于白天或者有外界光源的场合，优点是对比度高一些；
      全透模式：透过率约40%左右，必须配合背光使用（否则会看到屏下面的元件或者PCB），优点是背光亮度高；
      半透模式：介于反射和全透模式之间，透过率约30%，是否接背光都可以使用，比较灵活。
 
2、LCD段码屏有静态驱动和动态驱动的，请问如何区分？
      静态驱动：只有一个公共端COM，每个像素都是单独电极引出。优点是和动态驱动相比显示效果好一些，缺点是引脚多；
      动态驱动：超过2个以上公共端COM，每个电极至少控制2个以上的像素，需要时间分割扫描方式驱动。
 
3、LCD段码屏可以采用直流驱动吗？和LED数码管的驱动有什么不同？
       LED数码管：直流驱动，由公共端接在阳极或者阴极，有共阳或者共阴的区别；
     LCD液晶屏：交流驱动，公共端和驱动端都需要加交流方波信号，依靠改变两者的相位来控制对应的像素是否显示，这个是和LED数码管本质的区别，所以没有共阴或者共阳的说法。绝不能把公共端COM直接接地，通过控制驱动端接高电平来显示，这样子长时间工作容易损坏液晶屏。
 
4、LCD段码屏可以不用驱动芯片，直接单片机驱动吗？
     静态驱动的段码屏，如果单片机的IO口数量够的话，可以直接驱动；动态驱动的屏，由于需要时间分割的扫描方式驱动，而且偏压波形不好模拟，所以理论上是不能单片机直接驱动的。有些采用电阻分压的方式产生模拟偏压也可以用单片机直接驱动，但是程序编写太复杂，显示效果也不够理想，建议采用专用段码LCD驱动芯片，经常采用的是HT1621，价格低，3线SPI串口驱动，编程也简单。

https://omo-oss-file.thefastfile.com/portal-saas/new2023032116360282711/cms/file/87097da6-cbea-4e15-9f80-988d88ef57d3.zip


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