I'm confused as to why writing (and not writing) to
PORTB affects RB1 - it's an INPUT.  Are the PORTB
pins you've designated as output somehow connected
to RB1?

--- rituraj singh <rituraj@IITK.AC.IN> wrote:
> hello,
>
> I configured RB1 as an input pin. This pin was
> connected to a push-button
> switch (pulled up to Vdd by a 10K resistor).
>
> Case 1:
>         bsf STATUS, RP0
>         movlw B'00000111'
>         movwf TRISB
>         bcf STATUS, RP0
>         clrf PORTB
>
> Case 2:
>
> When the above code was written the voltage at RB1
> was some 1.56Volts.
> I changed the code to
>
>         bsf STATUS, RP0
>         movlw B'00000111'
>         movwf TRISB
>         bcf STATUS, RP0
>         movlw B'00000111'
>         movwf PORTB
>
> But the problem still existed. Voltage at RB1 was
> still some 1.56 volts.
>
> Case 3:
>
> However when the code was replaced by the following
> code, voltage at
> RB1 showed 4.97 Volts on switch open..
>
>         bsf STATUS, RP0
>         movlw B'00000111'
>         movwf TRISB
>         bcf STATUS, RP0
>
> Can any of you please tell why the voltage of RB1 is
> reducing in the
> first 2 cases?
>
> Also, in order to prevent this, do I need to
> initialise the output pins in
> PORTB individually?
>
> regards,
> Rituraj Singh
>
> --
> http://www.piclist.com hint: The PICList is archived
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> ways.  See http://www.piclist.com/#archives for
details.


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http://www.piclist.com hint: The PICList is archived three different
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