Introduction to Microprocessor
Hey everyone, in this section we will learn some basic concepts with respect to microprocessors.
Microprocessor in general words can be called as a general purpose digital computer Central Processing Unit (CPU). It is a silicon chip that comprises millions of transistors and other electronic components that processes millions of instructions per second. The input for a microprocessor is a binary data. Microprocessors are integrated electrical circuits that are capable of carrying out the instructions of a computer program. The instructions are given to a Microprocessor using Assembly Language Program (ALP).
Generally people find it difficult to differentiate between a Microprocessor and a Microcontroller, one of the simple difference is A microprocessor does not contain inbuilt memory whereas a Microcontroller has inbuilt memory. Hence a system designer using a general purpose microprocessor must add RAM, ROM, I/O Ports and Timer externally to make them functional.
Now, why do we need to know microprocessor? Many people throughout the world use smartphones, personal digital assistant devices (also known as PDA’s) and microcomputers. All of these utilize a key component : A Microprocessor.
A Microprocessor contains,
- Arithmetic and logic unit (ALU)
- General purpose registers
- Program counter
- Stack pointer
- Clock circuit
- Interrupt Circuits
Functions of each block :
- Arithmetic and logic unit (ALU) : This unit does the arithmetic operations such as addition, subtraction, and other operations such as AND or OR and also does the logical decisions.
- Accumulator : It is a device which stores a number and which on action with other number, adds the two and stores the sum. it can also sense the signal , clear and compliment etc.
- Working Register(s) : It is a short-term storage circuit, capacity of which is usually in one word. It may be group of flip-flops (stores a bit of data) connected together to store more than one signal level.
- Program Counter : It is a circuit which holds the address of a byte in memory. It also specifies the address at the next instruction to be fetched and executed.
- Stack Pointer :Stack is an area at internal Random Access Memory (RAM) that is used with some opcodes (assembly language instructions) to store or retrieve data quickly. Stack pointer is used to hold an internal ram address.
- Clock Circuit : It is a circuit that generates clock pulses by which all internal operations are synchronized.
- Interrupt Circuits : It is an electronic circuit which breaks in the normal flow of a system or routine and flow can be resumed from that point at later time.
Microprocessors are used extensively in the design of any computing facility. A number of devices can be interfaced (a shared boundary across which two or more separate components of a computer system exchange information) with a microprocessor to develop a complete system application.
In the next section we will be discussing about a 16-bit microprocessor which is called the 8086 microprocessor.