Greetings,

my led won't lit up too. i'm using pic16c84. the code run well in simulator,
but not in circuit. is there any problem with my circuit ?

** please select variable width font. thank you. excuse my drawing :) my first
ascii circuit (and pic project too )



5V
                            | -------------------|                        |
                            |1                   18 |                   RES
(3.3k)
                            |2                   17 |
|
                            |3        OSC1 16
|-------------------|---------CAP(22pF)------GND
                            |4                   15 |
           GND------|5 Vss   Vdd 14 |---5V
                            |6                   13 |
                            |7                   12 |
                            |8                   11
|                                                                   5V
                            |9          RB4  10
|-------------RES(470)------LED +------------ |
                            |------------------- |

configure to use RC osc, clear RB4 to sink current, thus turn LED on. can see
the PortB clear bit 4, TRISB is correct (all in mpsim). yet , in real circuit
it doesn't :(

regards,
ckchan


> clock if you want to use GPIO4 (pin 3) If you are
> using a clock source (not RC) then the oscillator
> has to be set to XT or LP, in which case GPIO4
> is used as OSC2.  If you are using a RC or
> Int_RC clock, then GPIO4 is available for use.
> (Hopefully your clock source is RC).
>
> Hope this helps,
>
> Michael Barker
> meb8208@rit.edu
>
> ----- Original Message -----
> From: "Rene Chauvet" <rchauvet@HOME.COM>
> To: <PICLIST@MITVMA.MIT.EDU>
> Sent: Wednesday, December 01, 1999 2:43 PM
> Subject: Re: led won't turn on
>
> > no I didn't
> >
> > ;                            _______  _______
> > ;                            |             \/              |
> > ;                Vdd --+ 1 <<           >> 8 +-- Vss
> > ;                            |                             |
> > ;             Clock  --+ 2 <<          >> 7 +-- disable signal (gpio0)
> > ;                            |                             |
> > ;               LED  --+ 3                >> 6 +-- data stream (gpio1)
> > ;                            |                             |
> > ; (gpio3) Reset   --+ 4 <<          >> 5 +-- gate output (grio2)
> > ;                            |                             |
> > ;                           +-------------------+
> >
> >
> > boot                  pin2     pin7
> >                              |          |
> >        movlw     b'11101111'   ; sets all pin as inputs exept pin 3
> >      tris          GPIO          ;turns led on
> >      bsf           led
> >
> >
> > ----- Original Message -----
> > From: Meric Ozcan <diehardee@USA.NET>
> > To: <PICLIST@MITVMA.MIT.EDU>
> > Sent: Wednesday, December 01, 1999 10:55 AM
> > Subject: Re: led won't turn on
> >
> >
> > Well you select the pin 4 as output...Your binary number is
> > backwards...
> >
> > Meric
> >
> >
> > >boot
> > >     movlw     b'11101111'   ; sets all pin as inputs exept pin 3
> > >     tris      GPIO          ;turns led on
> > >     bsf       led
> >
> > ____________________________________________________________________
> > Get free email and a permanent address at http://www.netaddress.com/?N=1
> >

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