Microprocessor Technology

DEPARTMENT OF COMPUTER APPLICATIONS
COLLEGE OF ENGINEERING,
THIRUVANANTHAPURAM

ASSEMBLY LANGUAGE PROGRAMMING
LAB – MANUAL

2005

INDEX
CONTENTS

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1. The 8085 microprocessor
1.1 Introduction
1.2 8085 Internal Architecture
1.3 8085 Pin Diagram
1.4 8085 Addressing Modes

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2. The 8085 Microprocessor Trainer Kit
2.1 Introduction
2.2 Specifications of STS -85 VLC
2.2.1 Hardware Specifications
2.2.2 Software Description

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3. 8085 Instruction Set Summary

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4. Entering a program and Execution procedure

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5. A Sample Program

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6. 8085 Instructions and Mnemonic codes

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7. Lab Exercises
7.1 Subtract two 8 bit numbers
7.2 Divide two 8 bit numbers
7.3 Palindrome checking
7.4 Sort in ascending order
7.5 Sort in descending order
7.6 Add two 16 bit numbers
7.7 Convert a BCD number to a binary number
7.8 Convert a binary number to a BCD number
7.9 Add ten 8 bit numbers
7.10 Multiply two 8 bit numbers
7.11 Largest of ten 8 bit numbers
7.12 Smallest of ten 8 bit numbers
7.13 Scroll a set of data in memory

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1. THE 8085 MICROPROCESSOR
1.1 Introduction
The 8085 microprocessor was made by Intel in mid 1970s. It was binary compatible with
8080 microprocessor but required less supporting hardware thus leading to less expensive microprocessor systems. It is a general purpose microprocessor capable of addressing 64k of memory. The device has 40 pins, require a +5V power supply and can operate with 3
MHz single phase clock. It has also a separate address space for up to 256 I/O ports. The instruction set is backward compatible with its predecessor 8080 even though they are not pin-compatible. 1.2 8085 Internal Architecture (Fig: 1)

The 8085 has a 16 bit address bus which enables it to address 64 KB of memory, a data bus 8 bit wide and control buses that carry essential signals for various operations.
It