A microprocessor controller unit is a circuitry that directs operations within a machine, be it a computer, household appliance or any other electrical and electronic device. Microprocessor controller unit enables a machine's logic units, memory, input and output devices to respond to the instructions received.
Microprocessor controller units work by receiving input information which is then converted into controller signals and passed on to the central processor. The central processor after analyzing the signals tells the machine's hardware what operations need to be carried out. These operations are then executed by the machine's hardware in tandem with the controller units.
These controller units are an inherent and essential part of all electronic and electrical devices that we use today. When invented, these were capable of analyzing only a limited number of instructions. With time, these have evolved exponentially and are today capable of millions of calculations per second. This breakneck speed has resulted in a common adage said about these units. i.e- every two years the ability of a microprocessor controller unit to perform calculations and analyze instructions doubles itself.
Functions Performed by Microprocessor Controller Units
To communicate with arithmetic logic unit and the main memory for carrying out stored program instructions.
To controller the flow of data between processor, memory and other peripheral parts.
The controller units also enable the loading of data and instructions residing in the secondary memory to the main memory as and when required.
To manage the translation of instructions into several micro instructions and channeling these towards execution and scheduling units.
Microprocessor controller units also enable/disable a machine's different interconnecting hardware controller signals as and when required during the execution of an instruction.
The controller units analyze the status of a running program and also end or disable the program if required.
Two Major Types of Microprocessor Controller Units
Hard wired controller units - Ideal for machines that have to execute a small and fixed set of instructions. Although faster compared to micro programmed units, hardwired controller units have very little flexibility, as a result these aren't widely used today.
Microprogram controller unit - Simpler and more flexible compared to hardwired units, these are ideal for executing large and varied set of instructions. Commonly found in computers, advanced machines etc. microprogram controller units are the most widely used today.
Instructions for Ensuring Long Functional Life of Microprocessor Controller Units
Make sure water or any liquid doesn't seep through the device into it's controller unit.
Periodically use a vacuum blower to clear dust from the controller units. Although microprocessor controller units aren't easily accessible on any machine, still some gaps are provided strategically on all machines, use these gaps to draw out dust.
Protect the electronic devices from voltage fluctuations.
Switch off a machine daily for some time; if not possible then at least switch off periodically. This will increase the longevity of it's microprocessor controller unit.