ALSTOM EP3-E-4-A 控制器

控制器分组合逻辑控制器和微程序控制器,两种控制器各有长处和短处。组合逻辑控制器设计麻烦,结构复杂，- 旦设计完成，就不能再修改或扩充，但它的速度快。微程序控制器设计方便，结构简单,修改或扩充都方便,修改一条机器指令的功能， 只需重编所对应的微程序;要增加一条机器指令,只需在控制存储器中增加一段微程序，但是，它是通过执行一段微程。 具体对比如下:组合逻辑控制器又称硬布线控制器，由逻辑电路构成，完全靠硬件来实现指令的功能。

The controller is divided into a combination logic controller and a microprogram controller, each with its strengths and weaknesses. The design of a combined logic controller is cumbersome and has a complex structure. Once the design is completed, it cannot be modified or expanded, but its speed is fast. The design of a microprogram controller is convenient, with a simple structure and easy modification or expansion. To modify the function of a machine instruction, only the corresponding microprogram needs to be reprogrammed; To add a machine instruction, simply add a microprogram to the control memory, but it is done by executing a microprogram. The specific comparison is as follows: a combination logic controller, also known as a hardwired controller, is composed of logical circuits and relies entirely on hardware to achieve the function of instructions.