ramp Counter ANALOGUE TO DIGITAL CONVERSION (ADC)

Thu May 16, 2013 4:37 pm

Code:: list p = 16f877 include <p16f877.inc> BANK0 macro bcf STATUS,RP0 bcf STATUS,RP1 endm BANK1 macro bsf STATUS,RP0 bcf STATUS,RP1 endm BANK2 macro bcf STATUS,RP0 bsf STATUS,RP1 endm BANK3 macro bsf STATUS,RP0 bsf STATUS,RP1 endm COUNT EQU 0x22 ;USED FOR COUNTING RESULT EQU 0x23 ORG 0 NOP GOTO START ORG 0x20 START CALL INIT REPEAT CLRF COUNT ;SET COUNT TO ZERO RAMP MOVF COUNT,W ;GET COUNT vALUE MOVWF PORTD ;AND OUTPUT TO DAC BTFSC PORTA,4 ;TEST COMP OUTPUT GOTO DONE ;IF NOT ZERo ; CoNVERS ION CoMPLETE INCF COUNT ;COtINT UP GOTO RAMP ;RAMP UP DONE MOVF COUNT,W ;GET COUNT MOVWF RESULT ;AND STORE GOTO REPEAT ;DO AGAIN ;PORT INIT ROUTINE INIT BSF STATUS,RP0 ;SET To BANK 1. CLRF TRISD ;SET PORT D To OUTPUT MOVLW 06 ;MAKE PoRT A DIGITAL MOVWF ADCON1 BSF TRISA,4 ;AND BIT A4 To INPUT BCF STATUS,RP0 ;BACK To BANK 0 RETURN END