8051- Microcontroller Experiments

Exp No: 17 AIM: To perform 8 bit arithmetic operations using 8051 microcontroller.

A) Addition B) Subtraction C) Multiplication D) Division

ADDITION MOV R0,#00 MOV A,#DATA1 ADD A, #DATA2 JNC LABEL INC R0 LABEL: MOV DPTR,#4150 MOVX @DPTR,A INC DPTR MOV A,R0 MOVX @DPTR,A HERE: SJMP HERE SUBTRACTION CLR C MOV B,#00 MOV A,#DATA1 SUBB A,#DATA2 JNC LABEL CPL A INC A INC B LABEL: MOV DPTR,#4150 MOVX @DPTR, A INC DPTR MOV A,B MOVX @DPTR,A HERE: SJMP HERE

MULTIPLICATION MOV A, #DATA1 MOV B, A MOV A, #DATA2 MUL AB MOV DPTR, #4150 MOVX @DPTR, A INC DPTR MOV A, B MOVX @DPTR, A LOOP: SJMP LOOP DIVISION MOV A, #DATA1 MOV B,A MOV A, #DATA2 DIV AB MOV DPTR, #4150 MOVX @DPTR, A INC DPTR MOV A, B MOV @DPTR, A LOOP SJMP LOOP

EXP NO: 18) INTERFACING OF DAC (Digital to Analog Converter)FOR GENERATIG WAVEFORMS 18 A) SQUARE WAVE GENERATION AIM. To generate square wave using DAC.

PROGRAM START MOV DPTR,#FFC8 MOV A,#00

MOVX @DPTR,A LCALL DELAY MOV A,#FF MOVX @DPTR,A LCALL DELAY LJMP START DELAY MOV R1, #05 LOOP MOV R2, #FF HERE DJNZ R2, HERE DJNZ R1, LOOP RET . 18 B) Generation of sawtooth wave Aim To create a sawtooth wave using DAC Program MOV DPTR, #FFC8 MOV A,#00 LOOP: MOVX @DPTR,A INC A SJMP LOOP

18 C) Generation of triangular wave AIM To generate triangular waveform using DAC. Program MOV DPTR, #FFC8 START MOV A, #00 LOOP1 MOV @DPTR,A INC A JNZ LOOP1 MOV A, #FF LOOP2 MOVX @DPTR,A DEC A JNZ LOOP2 LJMP START

Exp No: 19 ) Stepper Motor Interfacing

Aim To interface the stepper motor with 8051 and run it in clockwise and anticlockwise directions. Program Start: MOV DPTR,#4500 MOV R0,#04H JO : MOVX A,@DPTR PUSH DPH PUSH DPL MOV DPTR,#FFC0 MOV R2,#04 MOV R1,#0F DLY1: MOV R3,#0F DLY: DJNZ R3,DLY DJNZ R1,DLY1

DJNZ R2,DLY1 MOVX @DPTR,A POP DPL POP DPH INC DPTR DJNZ R0,JO SJMP START

Address For Clockwise

Rotation For Anticlockwise Rotation

4500 08 08

4501 01 02

4502 04 04

4503 02 01

Clock wise Anticlock wise Step A1 A2 B1 B2 Step A1 A2 B1 B2 1 2 3 4

1 0 0 0

0 0 1 0

0 0 0 1

0 1 0 0

8 1 4 2

1 2 3 4

1 0 0 0

0 0 1 0

0 1 0 0

0 0 0 1

8 2 4 1