Basic Stamp Speedometer? Fuel gauge?

Archiver

Basic Stamp Speedometer? Fuel gauge?

Hi!

I am working on a basic stamp application that requires the display of data graphically via dials and gauges, like a speedometer and a fuel gauge for instance.

It seems to me that a speedometer could be made using a stepper motor. Past discussion has revealed several methods of controling steppers that seem reasonable and relatively cheap. I figure the fuel gauge could be done using a voltage or current meter movement.· I am looking for suppliers for the following:

Very small stepper motors
Needles or other pointing devices to mount on the motors
Meter movements

Also, What is a good way to control a meter movement from the stamp? Do I need to use a D-A converter?

Thanks in advance!
--Scott

Archiver

Scott,

Automotive style meters I've seen (tachometers) use a crossed-coil air core
movement. It may be simple enough to home-brew, if that's your goal.
National used to make ICs to drive both coils of these movements from a
single voltage input. If they still do, your job would be greatly
simplified. National's app notes explain a lot of the technology involved
here. You may need a D-A converter to get voltage output from the Stamp,
but PWM techniques can sometimes eliminate this requirement...

<Also, What is a good way to control a meter movement from the stamp? Do I
need to use a D-A converter?>

Mike Hardwick, for Decade Engineering -- <http://www.decadenet.com>
Manufacturer of the famous BOB-II Serial Video Text Display Module!