A microprocessor is a component found in many electronic gadgets. It is the brain of a computer system and is in charge of completing a variety of tasks. You won’t be able to do anything with your computer until it has a microprocessor. It is an important part of the electronic industry and serves a variety of functions. It’s used to do things like addition, subtraction, interprocess communication, and input-output management. This can be classified based on the number of instructions it can generate in a second. A full overview of a microprocessor, its architecture, types, and uses have been provided here.
What is a Microprocessor?
A microprocessor is a computer processor that integrates the functionality of a central processing unit into a single integrated circuit (IC) or a few integrated circuits. Thus, a microprocessor is a multifunctional, clock-driven, register-based digital integrated circuit that accepts binary data as input, processes it according to the instructions stored in its memory, and then outputs the results. Microprocessors use both combinational logic and sequential digital logic to process numbers and symbols in the binary number system.
Here we are going to discuss the architecture of the 8085 microprocessor.
The 8085 is an 8-bit device. The 8085 is configured with a 16-bit address bus, an 8-bit data bus, a 16-bit stack pointer, a 16-bit programme counter, and eight-bit registers.
The device operates at a frequency of 3.2 MHz. The arithmetic and logic unit, timing and control unit, instruction register, decoder, interrupt control register, and serial input-output control are the primary components of the architecture. The ALU conducts various arithmetic and logic operations, while the timing and control unit coordinates all of the microprocessor’s components. Read More; AMD Ryzen 7000: Everything We Know About Zen 4 CPUs
Evolution of Microprocessor
- First Generation 4-bit Microprocessor
Intel invented the first microprocessor in 1971. It was known as the Intel 4004 since it was a 4-bit CPU.
- Second Generation 8-bit Microprocessor
In 1973, Intel released the Second Generation Processor, an 8-bit microprocessor. It was called the Intel 8008 because it had an 8-bit processor.
- Third Generation 16-bit Microprocessor
Intel released the third generation microprocessors in 1978, which were 16-bit microprocessors. The 80286 is a microprocessor of the third generation.
- Fourth Generation 32-bit Microprocessor
In 1985, the fourth generation of microprocessors was launched, and they were 32-bit. The most well-known 4th generation microprocessor is the 80386 (commonly known as i386 or just 386).
- Fifth Generation 64-bit Microprocessor
Fifth-generation microprocessors, often known as 64-bit microprocessors, were released in 1995 and are still in use today. Intel Pentium CPUs used a 64-bit architecture. Recent 64-bit microprocessors, such as Intel dual, quad, and octa-core microprocessors, utilise super scaling to provide great speed and performance.
List of Terms Used
The list of terms used in this is discussed below.
- Instruction Set
An instruction set is a collection of instructions or commands issued to a microprocessor. The instruction set serves as a bridge between software and hardware.
The bus is used to send data, address, and control information. This communication takes place in many components of the microprocessor. The bus in this case is divided into three types: data bus, control bus, and address bus.
- Instruction Per Cycle
The number of instructions that a CPU can execute in a single clock cycle is referred to as IPC.
The number of bits that may be handled in a single instruction is referred to as bandwidth.
- Clock Speed
The number of operations done by the CPU per second is referred to as clock speed. The clock speed is usually represented in megahertz (MHz).
- Word Length
The number of bits that can be processed by the CPU in a given amount of time is referred to as word length.
- Data Type
The sorts of data formats that the CPU may support are referred to as data types. For instance, binary, ASCII signed, and unsigned numbers.
Types of Microprocessor
Microprocessors are classified into three types: CISC, RISC, and EPIC. Prior to learning about them. Let us first define a microprocessor.
A microprocessor is essentially the computer’s brain. It is also known as a processor or CPU. Furthermore, a microprocessor is essentially a computer processor that is placed on a single integrated circuit (IC) (Integrated Circuit). It indicates that all of the processor’s functions are housed on a single chip. Furthermore, the basic function of a microprocessor is to read instructions from memory, decode them, process them, and output the results. While processing the data, it performs three essential activities.
We have three basic types of microprocessors. They are as follows:
1. CISC (Complex Instruction Set Computer)
The instructions are in a complex format, as the name implies. It means that a single instruction can include multiple low-level instructions in it. For instance, loading data from memory, storing data in memory and executing fundamental operations, to name a few examples. Furthermore, a single instruction can have numerous addressing modes. Furthermore, because a single instruction contains several operations, it uses a limited number of registers.
Examples of CISC are Intel 386, Intel 486, Pentium, Pentium Pro, Pentium II, etc. Read Also; Apple M2 Chip might not be the Next-Gen
Features of CISC Microprocessor:
- The instructions are lengthy.
- The number of instructions is around 100 to 200, more than that of a RISC CPU.
- Completing complex instructions takes more than four cycles up to roughly 120.
- Because the programme is executed sequentially, there is no pipelining feature (parallel execution).
- The instructions are carried out by a micro programme, which is where the complexity lies.
- In contrast to RISC fixed instructions, the instruction format and size can change.
- Because CISC programme code is simple and short, it requires less memory or RAM.
- It emphasised hardware rather than software or programming.
2. RISC (Reduced Instruction Set Computer)
As the name implies, the instructions in this are quite simple, and hence they execute rapidly. Furthermore, the instructions are completed in a single clock cycle and only use a few addressing modes. Furthermore, it employs several registers to reduce memory interaction.
Examples include the IBM RS6000, DEC Alpha 21064, DEC Alpha 21164, and others.
Features of RISC Microprocessor
- RISC microprocessor instructions are straightforward.
- The amount of instructions is limited to between 30 and 40, as implied by the name.
- Because the instructions are straightforward, it only takes one machine cycle to finish.
- In a RISC CPU, pipelining (parallel execution) is rather simple.
- Instructions have a limited and fixed format and size.
- The programme code is lengthy and requires extra memory due to the low number of instructions.
- It placed more attention on the software or compiler and less on the hardware load.
3. EPIC (Explicitly Parallel Instruction Computing)
It enables parallel computation of instructions through the use of compilers. Furthermore, the complicated instructions operate at lower clock frequencies. It also encodes the instructions in 128-bit bundles. Where each bundle comprises three 41-bit instructions and a 5-bit template. This 5-bit template specifies the type of instructions and which instructions can be executed concurrently.
Examples are IA-64 (Intel Architecture-64), etc.