Data Structure
Networking
RDBMS
Operating System
Java
MS Excel
iOS
HTML
CSS
Android
Python
C Programming
C++
C#
MongoDB
MySQL
Javascript
PHP
Physics
Chemistry
Biology
Mathematics
English
Economics
Psychology
Social Studies
Fashion Studies
Legal Studies
- Selected Reading
- UPSC IAS Exams Notes
- Developer's Best Practices
- Questions and Answers
- Effective Resume Writing
- HR Interview Questions
- Computer Glossary
- Who is Who
8085 program to convert 8 bit BCD number into ASCII Code
Now let us see a program of Intel 8085 Microprocessor. This program will convert 8-bit BCDnumbers to two digit ASCII values.
Problem Statement
Write 8085 Assembly language program where an 8-bit BCD number is stored in memory location 8050H. Separate each BCD digit and convert it to corresponding ASCII code and store it to the memory location 8060H and 8061H.
Discussion
In this problem we are using a subroutine to convert one BCD digit(nibble) to its equivalent ASCII values. As the 8-bit BCD number contains two nibbles, so we can execute this subroutine to find ASCIIvalues of them. We can get the lower nibble very easily by masking the upper nibble, and for the upper nibble, we have to mask the lower nibble at first, then rotate the register content dour times to the right to make, now we can change it to ASCII values.
Here we will put 26H as input, the program will return 32 and 36. These are the ASCII values of 2 and 6 respectively.
Note: This program can also take 8-bit binary number to ASCII values.
Input
| Address | Data |
|---|---|
| . . . | . . . |
| 8050 | 26 |
| . . . | . . . |
Flow Diagram
Program
| Address | HEX Codes | Labels | Mnemonics | Comments |
|---|---|---|---|---|
| 8000 | 31, 00, 81 | LXI SP, 8100 | Initialize SP | |
| 8003 | 21, 50, 80 | START | LXI H, 8050H | Initialize pointer with the first location of IN-BUFFER |
| 8006 | 11, 60, 80 | LXI D, 8060H | Initialize pointer with the first location of OUT-BUFFER | |
| 8009 | 7E | MOV A, M | Move the contents of 8050H to A | |
| 800A | 47 | MOV B, A | Copy A to B | |
| 800B | 0F | RRC | Rotate accumulator right 4 times | |
| 800C | 0F | RRC | ||
| 800D | 0F | RRC | ||
| 800E | 0F | RRC | ||
| 800F | CD, 1A, 80 | CALL ASCII | This subroutine converts a binary no. toASCII | |
| 8012 | 12 | STAX D | Store the contents of the accumulator specified the contents by DE register pair | |
| 8013 | 13 | INX D | Go to next location | |
| 8014 | 78 | MOV A, B | Copy B to A | |
| 8015 | CD, 1A, 80 | CALL ASCII | This subroutine converts a binary no. toASCII | |
| 8018 | 12 | STAX D | Store the contents of the accumulator specified the contents by DE register pair | |
| 8019 | 76 | HLT | Terminate the program | |
| 801A | E6, 0F | ASCII | ANI 0FH | Converts a BCD number to its corresponding ASCII value + 48 0 To 9 -----------------à48 To 57 + 55 A To F -----------------à 65 To 70 + 48 +7 So +48 is common but if the hex digit is between A to F then +7 is additional. |
| 801C | FE, 0A | CPI 0AH | ||
| 801E | DA, 23, 80 | JC CODE | ||
| 8021 | C6, 07 | ADI 07H | ||
| 8023 | C6, 30 | CODE | ADI 30H | |
| 8025 | C9 | RET | Returning control to the calling program |
Output
| Address | Data |
|---|---|
| . . . | . . . |
| 8060 | 32 |
| 8061 | 36 |
. . . | . . . |
1K+ Views
