STRING MANIPULATION

STRING MANIPULATION

AIM:

            To write an assembly language program using 8086 to find the number of

            Characters in a string, to move a byte from the source to destination and to store

             the string primitive.

ALGORITHM (LENGTH OF THE STRING):

1.      Start the program.

2.      Enter the opcodes from 1000.

3.      Enter the string starting from the location 1200.

4.      After entering the last character in the string enter the hexa value FF.

5.      Execute the program and check for result in 1100.

PROGRAM

ADDRESS	LABEL	OPCODE	MNEMONICS	OPERAND	COMMENTS
1000		BE, 00,12	MOV	SI, 1200	Initializing the string and the string starts in SI
1003		BA, FF, FF	MOV	DX, FFFF	Maximum location used for the entry of the string
1006		B4, FF	MOV	AH, FF	Moving the final data of array and also indicates the end of the string
1008	LOOP	42	INC	DX	Incrementing the string length by 1
1009		8A, 04	MOV	AL, [SI]	Get the string character to AL
100B		46	INC	SI	Increment the address location to get the next string
100C		38,C4	CMP	AH, AL	Check for the end of the string
100E		75,F8	JNZ	LOOP	Checking for the zero value.
1010		89,16,00,11	MOV	[1100], DX	Successful increment in the count else stores the string length.
1014		F4	HLT		Stop the program

ALGORITHM (STORE THE STRING PRIMITIVE):

1.      Start the program.

2.      Enter the program and execute it.

3.      Check if locations 1100 to 11FF contain 34.

4.      Stop the program.

PROGRAM:

ADDRESS	LABEL	OPCODE	MNEMONICS	OPERAND	COMMENTS
1000		B9, 00,01	MOV	CX, 0100	Moving the total no of location in which the primitive must be stored
1003		BF, 00,11	MOV	DI, OFFSET S_ARRAY	Moving the starting location value to DI
1006		B8, 34,00	MOV	AX, 0034	Moving the primitive value to AX
1009		FC	CLD		Clearing the data.
100A	L	AA	STOSB		Storing the string byte
100B		E2, FA	LOOP	L	Checking for the loop
100D		F4	HLT		Stop the program

ALGORITHM (MOVE):

1.      Start the program.

2.      Enter the program from the location 1000.

3.      Fill FF locations as stated above with a particular data, 41.

4.      Execute the program.

5.      Check if the contents are duplicated to another 255 locations using the compare command.

6.      Stop the program.

PROGRAM:

ADDRESS	LABEL	OPCODE	MNEMONICS	OPERAND	COMMENTS
1000		BE, 0E, 10	MOV	SI, OFFSET S_ARAY	Moving the source location from which the data should be moved
1003		BF, 0E, 11	MOV	DI, OFFSET D_ARRAY	Moving the ending location to which the data should be moved.
1006		B9, FF, 00	MOV	CX, 00FF	Total count location within which the data can be moved
1009		FC	CLD		Clearing the data.
100A	MOVE	A4	MOVSB		Moving the string byte.
100B		E2, FD	LOOP	MOVE	Continuous check of data
100D		F4	HLT		Stop the program

RESULT:

Thus the string operations move, store string primitive and to find the length of

 the string is executed and the results are verified.