8085 Program to Exchange 10 bytes
In this program we will see how to exchange a block of 10-byte data using 8085.
Problem Statement
Write 8085 Assembly language program to exchange a block of data, where block size is 10.
Discussion
The data are stored at location 8010H to 8019H and 9010H to 9019H. The location 8000H is holding the number of bytes to exchange. In this case number of bytes are 10D so it will be 0AH.
The logic is very simple, The HL and DE register pair is pointing the first and second data block respectively. By taking the data we are just swapping the values of each memory locations. Then repeating this process to swap two blocks completely.
Input
Address
| Data
|
|---|
.
.
.
| .
.
.
|
8000
| 0A
|
.
.
.
| .
.
.
|
8010
| 00
|
8011
| 11
|
8012
| 22
|
8013
| 33
|
8014
| 44
|
8015
| 55
|
8016
| 66
|
8017
| 77
|
8018
| 88
|
8019
| 99
|
.
.
.
| .
.
.
|
9010
| 84
|
9011
| 63
|
9012
| 12
|
9013
| 47
|
9014
| 48
|
9015
| AD
|
9016
| BC
|
9017
| 2A
|
9018
| 8F
|
9019
| 99
|
.
.
.
| .
.
.
|
Flow Diagram
Program
Address
| HEX Codes
| Labels
| Mnemonics
| Comments
|
|---|
F000
| 21, 10, 80
|
| LXI H, 8000H
| Point 8000Hto get byte count
|
F003
| 4E
|
| MOV C, M
| Load Count from memory
|
F004
| 21, 10, 80
|
| LXI H,8010H
| Point first block address
|
F007
| 11, 10, 90
|
| LXI D,9010H
| Point second block address
|
F00A
| 46
| LOOP
| MOV B, M
| Take element from first block to B
|
F00B
| 1A
|
| LDAX D
| Take element from second block to Acc
|
F00C
| 77
|
| MOV M, A
| Store Acc content to second block
|
F00D
| 78
|
| MOV A, B
| Load B to A
|
F00E
| 12
|
| STAX D
| Store into second block
|
F00F
| 23
|
| INX H
| Point to next address of first block
|
F010
| 13
|
| INX D
| Point to next address of second block
|
F011
| 0D
|
| DCR C
| Decrease the count variable
|
F012
| C2, 0A, F0
|
| JNZ LOOP
| When block is not completed, jump to LOOP
|
F015
| 76
|
| HLT
| Terminate the program
|
Output
Address
| Data
|
|---|
.
.
.
| .
.
.
|
8010
| 84
|
8011
| 63
|
8012
| 12
|
8013
| 47
|
8014
| 48
|
8015
| AD
|
8016
| BC
|
8017
| 2A
|
8018
| 8F
|
8019
| 99
|
.
.
.
| .
.
.
|
9010
| 00
|
9011
| 11
|
9012
| 22
|
9013
| 33
|
9014
| 44
|
9015
| 55
|
9016
| 66
|
9017
| 77
|
9018
| 88
|
9019
| 99
|
. . . | . . . |
Published on 21-Jan-2019 14:42:26
