Hi Tony, thanks for your attention.
My doubts it is: Will it be that my initial configuration this correct one?
          __CONFIG _CP_OFF & _WDT_OFF & _BODEN_OFF & _PWRTE_OFF & _XT_OSC &
  _WRT_ENABLE_OFF

The led realy doesn't blink. I put on  the osciloscope in the out (PORTC6),
and nothing doesn't happen, it just is in 0.
I am using PICSTART PLUS for play the PIC16F873.
Regards.
Anbar.

> -----Mensagem Original-----
> De: Tony Nixon <Tony.Nixon@ENG.MONASH.EDU.AU>
> Para: <PICLIST@MITVMA.MIT.EDU>
> Enviada em: Segunda-feira, 7 de Fevereiro de 2000 20:03
> Assunto: Re: First Project with PIC16F87x doesn't work
>
>
> > anbarsystem@ZAZ.COM.BR wrote:
> > >
> > > Hi All,
> > > My first project with the PIC16F87X doesn't work. I am simply trying
to
> do a
> > > conversion A/D in the PORTA0 and show it  in PORTB with leds.Also a
led
> > > blinking in the PORTC6 using TMRO overflow. I'm using a 4MHZ cristal.
> > >
> > > See my Codes below.
> > >
> > > #DEFINE LED     PORTC6
> > >
> > >         list p=16f873
> > >
> > >         include "p16f873.inc"
> > >
> > >          __CONFIG _CP_OFF & _WDT_OFF & _BODEN_OFF & _PWRTE_OFF &
_XT_OSC
> &
> > > _WRT_ENABLE_OFF
> > >
> >
> > Add this..
> >
> > Temp     equ 20h        ; temp timer register
> >
> >
> > > ;----------------------------------------------------
> > > ; Start at the reset vector
> > >         org 0x000
> > >
> > > Start:
> > >         clrf PORTA
> > >         clrf PORTB
> > >         clrf PORTC
> > >         bsf STATUS,RP0
> > >         movlw B'00000111'     ;TMR0 prescaler, 1:256
> > >         movwf OPTION_REG
> > >         movlw b'00000001'     ;PA0=IN
> > >         movwf TRISA
> > >         movlw b'00000000'
> > >         movwf TRISB                 ;PB=OUT
> > >         movlw b'00000000'       ;PC=OUT
> > >         movwf TRISC
> >
> > Try this value for ADCON1
> >
> >          movlw b'00000100'          ; RA0,1,3 = A2D, left justify
> >
> > >         movlw b'00001110'     ;VREF+ VDD E VREF- VSS, PORTA0  A/D IN
> > >         movwf ADCON1
> > >         bcf STATUS,RP0      ;Fosc/8, A/D ON
> >
> > Try this value for ADCON0
> >
> >          movlw b'11000001'          ; A2D = on, internal RC, chan 0
> >
> > >         movlw b'01000001'
> > >         movwf ADCON0
> > >
> >
> >
> > The LED may appear not to blink because the time it takes for TMR0 to
> > overflow at 4MHz is about 65mS. Try this...
> >
> > > MAIN:
> >           movlw d'10'
> >           movwf Temp
> > >         clrf TMR0
> > TimeWt    btfss INTCON,T0IF     ;Wait for Timer0 to timeout
> > >         goto $-1
> > >         bcf INTCON,T0IF
> >
> >           decfsz Temp
> >           goto TimeWt
> >
> > >         btfss LED
> > >         goto LED_ON
> > >         bcf LED
> > >         goto SET_AD
> > >
> > > LED_ON:
> > >         bsf LED
> > >
> > > SET_AD:
> > >         bsf ADCON0,GO     ;Start A/D conversion
> > >
> >
> > Try this code for conversion complete
> >
> > Wait     nop
> >          btfsc ADCON0,GO       ; (bit 2) = 0, conv is complete
> >          goto Wait
> >
> > > Wait:
> > >         btfss PIR1,ADIF     ;Wait for conversion to complete
> > >         goto $-1
> > >
> > >         movf ADRESH,W     ;Write A/D result to PORTB
> > >         movwf PORTB
> > >         goto MAIN
> > >
> > > I would appreciate it if someone could make a suggestion.
> > >
> > > Thanks in advanced.
> > > Anbar.
> >
> > --
> > Best regards
> >
> > Tony
> >
> > http://www.picnpoke.com
> > mailto:sales@picnpoke.com
>