potentiometer design issue

[sirron]

Hi
i am trying to work out a problem.
i have a 10k potentiometer and what i want to attach to it is a digital display the will show the value that the potentiometer is at, Sounds simple enough so far.

the trouble is i want the display to only read between 0-160 ohms.
so for example
pot = 10k reading is 160
pot = 5k reading is 80
pot = 200 reading is 3.2 and so on

how can i achieve this

thanks

[piratepaul]

AD converter and a binery to digital encoder and some 7 set displays.
What you have said is confusing, do you just want to read the values, or are they running something that you want to keep an eye on?
To convert to a voltage you are going to have to run a small current through them, and convert the voltage to digital and process from there.

[Pauldf]

You'll also need some sort of span control so you'll need to use something like op amps with more potentiometers to do this.

[piratepaul]

What's a span control?

Run a current through the resistor, take the voltage, convert to digi code, convert to denary, and encode for 7 set display.
You could treat the pot as 2 resistances and calculate the position of the wiper if need be ...

Wots it for?

tar&stuff.

[Pauldf]

Span is how we setup (or calibrate) the width of the signal in instrumentation, we also normally have a zero pot but if zero is zero then we don't really need it.

For example we may have a 0 to 100 degrees system with a platinum resistance thermometer giving out 100R at zero and 138.5R at 100 degrees.
So on our display we would calibrate the zero so 100R reads zero and the span so 138.5R reads 100 degrees.