Reading a temp sensor...
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Hello, I'm trying to read a resistor based temp sensor. It goes from
about 700ohms (hot) to 4000 ohms (ice cold). My problem is tring to
get the calculation of the reaction time. I know I'm doing it wrong
and simply don't know what value cap I should be using. Can anyone
help?
Thanks,
Cozz
about 700ohms (hot) to 4000 ohms (ice cold). My problem is tring to
get the calculation of the reaction time. I know I'm doing it wrong
and simply don't know what value cap I should be using. Can anyone
help?
Thanks,
Cozz
Comments
wrote:
> Hello, I'm trying to read a resistor based temp sensor. It goes
from
> about 700ohms (hot) to 4000 ohms (ice cold). My problem is tring to
> get the calculation of the reaction time. I know I'm doing it wrong
> and simply don't know what value cap I should be using. Can anyone
> help?
>
> Thanks,
> Cozz
Help?
Give us some more details. What sensor, what voltage are you giving it? What
sensor are you using? From your post it seems you want to use the RCTIME
command, not an ADC. Is this correct?
Jonathan
www.madlabs.info
Original Message
From: "cozz4ever" <cozz.home@v...>
To: <basicstamps@yahoogroups.com>
Sent: Saturday, December 06, 2003 5:30 PM
Subject: [noparse][[/noparse]basicstamps] Re: Reading a temp sensor...
> --- In basicstamps@yahoogroups.com, "cozz4ever" <cozz.home@v...>
> wrote:
> > Hello, I'm trying to read a resistor based temp sensor. It goes
> from
> > about 700ohms (hot) to 4000 ohms (ice cold). My problem is tring to
> > get the calculation of the reaction time. I know I'm doing it wrong
> > and simply don't know what value cap I should be using. Can anyone
> > help?
> >
> > Thanks,
> > Cozz
>
>
> Help?
>
>
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>
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>
>
>
>
sensor will not be pluged to anything else other than the stamp. I am
feeding it 5 volts from the Vss socket on the stamp board. The cap is
on Vdd and merges with the other wire of the sensor and both go to a
2220ohm resistor to pin 0. Yes I'm using RCTIME like the book says.
But I'm lost as to what the value for the cap should be. I tried to
do the calculation (RC time)on the book but I think I'm doing it
wrong. I'm using a 4.7 uF. I think it should be a lot lower than that.
Thanks,
Cozz
--- In basicstamps@yahoogroups.com, "Jonathan Peakall"
<jpeakall@p...> wrote:
> Cozz,
>
> Give us some more details. What sensor, what voltage are you giving
it? What
> sensor are you using? From your post it seems you want to use the
RCTIME
> command, not an ADC. Is this correct?
>
> Jonathan
>
> www.madlabs.info
>
>
Original Message
> From: "cozz4ever" <cozz.home@v...>
> To: <basicstamps@yahoogroups.com>
> Sent: Saturday, December 06, 2003 5:30 PM
> Subject: [noparse][[/noparse]basicstamps] Re: Reading a temp sensor...
>
>
> > --- In basicstamps@yahoogroups.com, "cozz4ever" <cozz.home@v...>
> > wrote:
> > > Hello, I'm trying to read a resistor based temp sensor. It goes
> > from
> > > about 700ohms (hot) to 4000 ohms (ice cold). My problem is
tring to
> > > get the calculation of the reaction time. I know I'm doing it
wrong
> > > and simply don't know what value cap I should be using. Can
anyone
> > > help?
> > >
> > > Thanks,
> > > Cozz
> >
> >
> > Help?
> >
> >
> > To UNSUBSCRIBE, just send mail to:
> > basicstamps-unsubscribe@yahoogroups.com
> > from the same email address that you subscribed. Text in the
Subject and
> Body of the message will be ignored.
> >
> >
> > Your use of Yahoo! Groups is subject to
http://docs.yahoo.com/info/terms/
> >
> >
> >
> >