用户定义功能块(UDFB)之于可编程逻辑控制器就像功能之于微控制器一样。两者都是用于简化代码的结构，使其更容易编写，故障排除和维护。它们也是允许代码在将来被重用的基本结构。 本文引用地址： 本文概述了在Arduino Opta 1中使用的简单UDFB的构造。

On the surface, a programmable logic controller (PLC) might seem like nothing more than a generic microcontroller, perhaps outfitted to operate in industrial settings with things like high ...

If your usual tools are the Arduino and the Raspberry Pi, you might find it surprising that the industrial world tends to run on Programmable Logic Controllers, or PLCs. You can think of a PLC as a ...