📅  最后修改于: 2021-01-07 05:42:58             🧑  作者: Mango
处理器是嵌入式系统的心脏。它是处理数据后接受输入并产生输出的基本单元。对于嵌入式系统设计人员来说,必须具有微处理器和微控制器的知识。
处理器具有两个基本单元-
CU包括用于从存储器中获取指令的获取单元。 EU具有执行与数据传输操作和从一种形式到另一种形式的数据转换有关的指令的电路。
EU包括算术和逻辑单元(ALU),还包括执行程序控制指令(例如中断或跳转到另一组指令)的电路。
处理器运行取指的周期,并按照与从内存中取指相同的顺序执行指令。
处理器可以属于以下类别-
通用处理器(GPP)
专用系统处理器(ASSP)
专用指令处理器(ASIP)
专用集成电路(ASIC)或超大规模集成电路(VLSI)电路上的GPP内核或ASIP内核。
微处理器是具有CPU的单个VLSI芯片。此外,它还可能具有其他单元,例如,指导,浮点处理算术单元和流水线单元,它们有助于更快地处理指令。
上一代微处理器的获取和执行周期由大约1 MHz的时钟频率指导。处理器现在以2GHz的时钟频率运行
微控制器是单芯片VLSI单元(也称为微型计算机),尽管计算能力有限,但具有增强的输入/输出能力和许多片上功能单元。
CPU | RAM | ROM |
I/O Port | Timer | Serial COM Port |
微控制器特别用于嵌入式系统中,用于带有片上程序存储器和设备的实时控制应用。
现在让我们看一下微处理器和微控制器之间最明显的区别。
Microprocessor | Microcontroller |
---|---|
Microprocessors are multitasking in nature. Can perform multiple tasks at a time. For example, on computer we can play music while writing text in text editor. | Single task oriented. For example, a washing machine is designed for washing clothes only. |
RAM, ROM, I/O Ports, and Timers can be added externally and can vary in numbers. | RAM, ROM, I/O Ports, and Timers cannot be added externally. These components are to be embedded together on a chip and are fixed in numbers. |
Designers can decide the number of memory or I/O ports needed. | Fixed number for memory or I/O makes a microcontroller ideal for a limited but specific task. |
External support of external memory and I/O ports makes a microprocessor-based system heavier and costlier. | Microcontrollers are lightweight and cheaper than a microprocessor. |
External devices require more space and their power consumption is higher. | A microcontroller-based system consumes less power and takes less space. |