Interfacing of ADC with 8051 Microcontroller

ADC (Analog To Digital Conversion)

ADC takes an analog signal, such as an electrical current, and digitize it into a binary format so that the machine can understand it.

Here we have aprogram to interface an ADC with 8051 microcontroller using a simlator.

ORG 00H
SETB P2.2
MOV P1,#0FFh
MOV A,#06H
ACALL CMD
ACALL DELAY
MOV A,#0EH
ACALL CMD
ACALL DELAY

MOV A,#38H
ACALL CMD
ACALL DELAY

GO:
ACALL ADCDATA
ACALL HEXTOASCII
ACALL DISPLAY
ACALL DELAY
ACALL DELAY
ACALL DELAY
ACALL DELAY
ACALL DELAY
ACALL DELAY
ACALL DELAY
ACALL DELAY
ACALL DELAY
ACALL DELAY
ACALL DELAY
ACALL DELAY
ACALL DELAY
ACALL DELAY
ACALL DELAY
ACALL DELAY
ACALL DELAY
ACALL DELAY
ACALL DELAY
ACALL DELAY
ACALL DELAY
ACALL DELAY
ACALL DELAY
SJMP GO

ADCDATA: CLR P2.1
SETB P2.1
JB P2.2,$
CLR P2.0
ACALL DELAY
MOV A,P1
SETB P2.0
RET

HEXTOASCII:
MOV B,#10
DIV AB
MOV R5,B
MOV B,#10
DIV AB
MOV R6,B
MOV R7,A

MOV A,R5
ORL A,#30H
MOV R2,A
MOV A,R6
ORL A,#30H
MOV R1,A
MOV A,R7
ORL A,#30H
MOV R0,A
RET


CMD:

MOV P3,A
CLR P2.3
CLR P2.4
SETB P2.5
ACALL DELAY
CLR P2.5
RET

DATA1:
MOV P3,A
SETB P2.3
CLR P2.4
SETB P2.5
ACALL DELAY
CLR P2.5
RET

DELAY:
MOV R4,#0FFH
DJNZ R4,$
MOV R4,#0FFH
DJNZ R4,$
RET

DISPLAY:
MOV A,#01H
ACALL CMD
ACALL DELAY
MOV A,#80H
ACALL CMD
ACALL DELAY

MOV A,R0
ACALL DATA1
MOV A,R1
ACALL DATA1
MOV A,R2
ACALL DATA1
RET
END