This document discusses the architecture and programming of microprocessors. It focuses on the Intel 8085 8-bit microprocessor. Key points include: - The 8085 has an 8-bit data bus and 16-bit address bus, allowing access to 64KB of memory. It has accumulator, flag, program counter and other registers. - Assembly language is used to program the 8085 by mapping mnemonics to machine code instructions. Various I/O devices can be interfaced like keyboards and timers. - The document outlines chapters covering the 8085 architecture, programming, interfacing I/O, and advanced microprocessors. It provides background on microprocessor applications and system components like memory, input, output and the

1. MICROPROCESSOR &
INTERFACES

2.  1. Understand the architecture of microprocessor
system
 2. Understand the assembly language
 3. Can program the microprocessor (8085) using
assembly language
 4. Can interface the microprocessor to external
devices such as key board, LEDs, timers, counters
etc.
 5. Can apply the microprocessor in embedded
system

3.  1)Introduction-chapter 1
 2) Internal Microprocessor Architecture –
 chapter 2 (Intro to 8085ALP),
 chapter 3(Architecture),
 chapter 4,(Interface Memory)
 chapter 5 (Interface I/O)
 3) Microprocessor Programming-
 chapter 6, chapter 7,(Instructions)
 chapter 8(Counter and Delays),
 chapter 9(Stack and Subroutines)

4.  4)Interfacing I/Os –
 chapter 12(Interrupts),
 chapter 14(Interface 8155 I/O & Timer, 8279
Keyboard/Display Interface), Programmable Interface
Devices
 chapter 15(General Purpose Programmable
Peripherals)(Programmable peripheral interface,
Interval timer, PIC, DMA)
 5) Advanced Microprocessors
Text Book: Microprocessor Architecture,
programming And Application With The 8085.
Ramesh S. Gaonkar

5.  Intel 8085 is an 8 bit microprocessor
introduced by Intel in 1977.
 The 8085 follows the von Neumann
architecture with a 16 bit address bus and 8
bit data bus.
 It can access 216
(65536) individual 8 bit
memory locations (64KB)
 Has built in register:
 A (accumulator), B,C,D,E,H and L (8 bit)
 Special purpose register: 16 bit program counter,
stack pointer, and 8 bit flag register

6.  Share memory for program and data with
one data bus and one address bus between
processor and memory.
 Instruction and data have to be fetched in
sequential order, limiting the operation
bandwidth.
 Its design is simpler than that of architecture.
 It is mostly used to interface to external
memory.

7.  Uses physically separate memories for
instruction and data, requiring dedicated
buses for each of them.
 Instruction and operands can be fetched
simultaneously.
 Different program and data bus widths are
possible, allowing program and data memory
to be better optimized to the architectural
requirements.

11.  Has single 5volt power supply
 Clock oscillator and system controller were
integrated on the chip.
 The CPU included serial I/O port.
 Multiple version of 8085 microprocessor.

12.  Original version without suffix A is from Intel.
 Then replaced by 8085A, HMOS version and CMOS
version.
 Second source manufacturer: AMD, mitsubishi,
NEC, OKI, Siemens, Toshiba

14. μp is a programmable integrated device that has
computing and decision making capability, similar to
CPU of a computer.
Can be:
 1) embedded in a larger system
 2) a stand alone unit controlling processor
μp communicates and operates in the binary number
0 & 1, called bits.
Each μp has a fixed set of instructions in the form of
binary patterns called machine language.
The binary instructions are given abbreviated names,
called mnemonics, form the assembly language.

15. A μp is a multipurpose, programmable,
clock-driven, register based electronic
device that reads binary instructions
from a storage device called memory,
accepts binary data as input and process
data according to those instructions and
provides results as output.

16.  A typical programmable machine can be
represented with 4 components:
 Microprocessor
 Memory
 Input
 Output
 These 4 components will form a system.
 The physical components --> hardware
 A set of instructions program
 A group of program is called software

17. The μp applications are clssified
primarily in two categories:
 Reprogrammable system (PC)
 Embedded system (washing machine)
In embedded system, μp is a part of a
final product and is not available for
reprogramming to the end user.

18.  μp operates in binary digits, 0 & 1, known as
bits.
 Represented in terms of electrical voltage.
 A group of bits called a word.
 μp with an 8 bit word is known as an 8 bit μp.

19. μp is a primary components of a computer.
The computer has 4 components:
 Memory
 Input
 Output
 CPU
CPU contains various registers to store data , the
ALU to perform arithmetic and logical operations,
instruction decoders, counter and control lines.

21.  Is the area of microprocessor where various
computing functions are performed on data
such as addition, subtraction, logic
operations (AND, Or and exclusive OR).

22.  This area of μp identified by letters such as B,
C, D, E,H and L.
 Used to store data temporarily during the
execution of a program and are accessible to
the user through instructions.

23.  Provides the necessary timing and control
signals to all the operations in the
microcomputer.
 Control the flow of data between μp and
memory and peripheral.

24.  Two types of memory:
 ROM (read only memory)
 RAM ( random access memory)

25.  Used to communicate with the outside world.
 The I/O device is knows as peripherals.
 Input devices:
 Keyboard
 Switches
 ADC
 Output devices:
 LED
 DAC
 LCD

26.  Is a communication path between
microprocessor and peripherals.
 A group of wires to carry bits.
 Three types of bus:
 Address bus
 Data bus
 Control bus

28.  Programming languages that are intended to
be machine –independent are called high
level language.
 Examples: BASIC, PASCAL, C, C++ and Java.
 Instructions written in these langugaes are
called statements rather than mnemonics.
 Compiler is used to convert the statements to
binary languages.

29.  This translation in the machine language is called
object code.
 Compiler requires large memory space because the
statements requires several machine codes to
translate it to binary.
 There is one to one correspondence between the
assembly language mnemonics and the machine
code. Thus assembly language are compact and use
less memory space.
 The advantage of high level language is in
troubleshooting (debugging) programs. Much easier
to find errors in a program, in high level language.
 Application: traffic control-assembly language
 Application: video games, billing where memory is
not a limitation- high level language