Central processing unit cpu is carved on a single chip is called a microprocessor. The 8085 checks the status of intr signal during execution of each instruction. The 8 most significant bits of the address are transmitted by the address bus, pins a 8, to a 15. The address and data bus are multiplexed in this processor which helps in providing more control signals. This was introduced by the intel company in the year 1977 to 1990.
As some of the architectural drawbacks associated with 8080 was also. If intr signal is high, then 8085 completes its current instruction and sends an active low interrupt acknowledge signal inta if the interrupt is enabled. Jun 05, 2015 4262015 bus structure of 8085 microprocessor 8085 microprocessor complete tutorial structure of8085 mi. The functional components of a cpu are arithmetic logic unit alu, control and timing units, registers are found in a single integrated circuit called ic. Unit1 introduction to 8086 ece department microprocessors and microcontrollers page 2 iv address bus. The 5 in the model was added as it requires plus 5 voltages. A processor with longer word length is more powerful and can process data at a faster speed as compared to processor with shorter word length. To find the smallest number in an array of data using 8085 instruction set. Its data bus width is 8bit and address bus width is 16bit, thus it can address 216. The following image depicts the pin diagram of 8085 microprocessor. The memory interfacing in 8085 is used to access memory quite frequently to read instruction codes and data stored in memory. Architecture and functional block diagram of 8085 microprocessor microprocessor 8085 architecture 8085 architecture 8085 microprocessor the functional block diagram or architecture of 8085 microprocessor is very important as it gives the complete details about a microprocessor. The first 8 lines of address bus and 8 lines of data bus are multiplexed ad0 ad7.
Memory is an integral part of a microprocessor system, and in this section, we will discuss how to interface a memory device with the microprocessor. As discussed earlier, 8085 microprocessor was introduced by intel in the year 1976. Bus structure of 8085 microprocessor the microprocessor mpu performs various operations with peripheral devices or a memory location by using three sets of communication lines called buses. This microprocessor exhibits some unique characteristics and this is the reason it still holds popularity among the microprocessors basically, 8085 was the first commercially successful microprocessor by intel. Introduction to microprocessor 6 the 8085 interrupts the 8085 has 5 interrupt inputs. The memory interfacing in 8085 is used to access memory quite frequently to. Lecture note on microprocessor and microcontroller theory and. The data bus is used to transfer data between memory and. Hardware architecture of 8085 microprocessor rmd engineering. The pins of a 8085 microprocessor can be classified into seven groups. In this article you will get to know about the definition, architecture, block diagram and working of 8085 microprocessor. Pdf intel 8085 microprocessor architecture anurudh. A15a8, it carries the most significant 8bits of memoryio address.
Nov 29, 2016 the 8085 bus structure the 8bit 8085 cpu or mpu micro processing unit communicates with the other units using a 16bit address bus, an 8bit data bus and a control bus. Thus has the ability to address 4 gb or 2 32 of physical memory. Before knowing about the 8085 architecture in detail, lets us briefly discuss about the basic features of 8085 processor 8085 microprocessor is an 8bit microprocessor with a 40 pin dual in line package. Microprocessor communicates with memory and other devices input and output using three buses. This microprocessor is an update of 8080 microprocessor. Bus structure of 8085 microprocessor 8085 microprocessor.
In 8085 microprocessor all these functions are performed by using three sets of communication lines called buses. List of all microprocessor 8085 all program with examples. The microprocessor performs primarily four operations. The size of the address bus determines the size of memory, which can be used. This means that microprocessor 8085 can transfer maximum 16 bit address which means it can address 65,536 different memory locations. The address bus carries the address of memory location to be written or to be read from. Jan 07, 2009 the 8085 also supports the interrupt structure of the 8080, with the interrupt and interrupt acknowledge lines. Diagram to represent bus organization system of 8085 microprocessor. It was compatible with intel 8080 but needed less support of the hardware. The address and data busses the address bus has 8 signal lines a8 a15 which are unidirectional.
The internal architecture of 8085 includes the alu, timing and control unit, instruction register and decoder, register array, interrupt control and serial io control. Draw the architecture of 8085 and mention its various functional blocks. Bus is a group of conducting wires which carries information, all the peripherals are connected to microprocessor through bus. Pdf intel 8085 microprocessor architecture anurudh kashya. Let us discuss the architecture of 8085 microprocessor in. Were continuing with internal microprocessor structure. In the grand scheme of things here we have the microprocessor memory and the three buses. The 8bit instruction register is used to hold the opcode hexadecimal.
It depends upon the width of internal data bus, registers, alu etc. Its data bus is 8bit wide and hence, 8 bits of data can be transmitted in parallel from or to the microprocessor. Thus has the ability to address 4 gb or 2 32 of physical memory multitasking and protection capability are the two key characteristics of 80386 microprocessor. An 8bit microprocessor can process 8 bit data at a time. These signals are used to identify the nature of operation. It provides serial interfacing with serial input data sid and serial output. Flag register of 8085 microprocessor with example 8085. In the 85, however, these lines are made available to the internal data bus of the mp instead of being connected directly to the timing and control logic. A processor with longer word length is more powerful and can process data at a faster speed as compared to. In 8085, the lower 8bit address bus a 0a 7 and data bus d 0d 7 are multiplexed to reduce number of external pins. Microprocessor multiple choice questions and answersintel. Address bus is unidirectional because data flow in one. In response to the inta signal, external logic places an instruction opcode on the data bus. In this you can get access to microprocessor 8085 programming tutorial which.
Microprocessor internal structure microprocessors video lecture. Microprocessor 8085 communicates via its address bus of 2bytes width the. On these lines the cpu sends out the address of the memory location that is to be written to or read from. It has 16bit address bus and hence can address up to 216 65536 bytes 64kb memory locations through a0a15. It is an 8 bit general purpose microprocessor that can easily store 64k bite of memory. The 8085 also supports the interrupt structure of the 8080, with the interrupt and interrupt acknowledge lines. The 8080 processor was updated with enabledisable instruction pins and interrupt pins to form the 8085 microprocessor. The bus over which the cpu sends out the address of the memory location is known as address bus. Data bus is used to transfer data within microprocessor and memoryinput or. So it can be used to carry the 8 bit data starting from 00000000h00h to 11111111hffh.
Aug 08, 2018 the 8085 checks the status of intr signal during execution of each instruction. Memory interfacing in 8085 memory structure wait state. Bus structure of 8085 microprocessor this application consists the basic example of 8085 microprocessor. It is a group of wires or lines that are used to transfer the addresses of memory or io devices. Bus organisation of 8085 and general purpose registers is covered in this lesson. Intel 8085 microprocessor architecture signals addressing modes. The microprocessor unit performs primarily four operations. Lecture note on microprocessor and microcontroller theory vssut.
In this tutorial, we will discuss the architecture, pin diagram and other key concepts of. Ad7ad0, it carries the least significant 8bit address and data bus. Feb 20, 2017 8085 microprocessor bus organization and initiated operation. Introduction to 8085 microprocessor computer science. List of all microprocessor 8085 all program with examples so guys here are the list of 8085 programs for beginners who are currently learning 8085 microprocessor and also for those who are looking for8085 microprocessor programs pdf here is all and you can collect it. Bus organization of 8085 microprocessor geeksforgeeks. Its data bus width is 8bit and address bus width is 16bit, thus it can address 216 64 kb of memory. Lecture note on microprocessor and microcontroller theory. Tutorial on introduction to 8085 architecture and programming. In intel 8085a microprocessor ale signal is made high to. Click download or read online button to get 8085 microprocessor interfacing and applications book now. Memory organisation in computer architecture array multiplier in digital logic.
This site is like a library, use search box in the widget to get ebook that. The address bus consists of 16, 20, 24, or more parallel signal lines. Data and address bus the intel 8085 is an 8bit microprocessor. But due to this, external hardware is required to separate. I syllabus introduction to 8085 intel 8085 microprocessor.
Architecture and functional block diagram of 8085 microprocessor. It means bits flowing occurs only in one direction, only from microprocessor to peripheral devices. The 8085 bus structure the 8bit 8085 cpu or mpu micro processing unit communicates with the other units using a 16bit address bus, an 8bit data bus and a control bus. The schematic representation of the 8085 bus structure is as shown in fig. In intel 8085 microprocessor, address bus was of 16 bits. Jan 23, 2018 list of all microprocessor 8085 all program with examples so guys here are the list of 8085 programs for beginners who are currently learning 8085 microprocessor and also for those who are looking for8085 microprocessor programs pdf here is all and you can collect it. To communication with a memory, for example to read instruction from memory location. In examining the internal structure of a microprocessor, the elements that are needed to drive the address bus are what were looking at this point is the address bus. Enable the data bus to be used as low order address bus. Microprocessor lecture 16 microprocessor architecture and. They are address bus, data bus and control bus as shown. It is a group of conducting wires which carries address only. Microprocessor internal structure microprocessors video.