fingerprint sensor
Moderators: adafruit_support_bill, adafruit

fingerprint sensor

by bogeyer on Sat Dec 29, 2012 11:28 pm

On the Adafruit fingerprint sensor after i power it up, it works just fine, but after about 1:00 minute it just shuts off. how do i make it so it runs all the time as long as it has power.
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Re: fingerprint sensor

by adafruit_support_bill on Sun Dec 30, 2012 7:51 am

What sketch are you running? The "fingerprint" example should run continuously - looking for fingerprints.
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Re: fingerprint sensor

by bogeyer on Sun Dec 30, 2012 12:11 pm

that is the one im running, i did make some altercations which allowd the arduino to turn an led on when i got a match but that work, and thats was only a few lines of code. I didn't rely make any major changes. I will upload the orgianal fingerprint code and see if that works.
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Re: fingerprint sensor

by bogeyer on Thu Jan 03, 2013 5:08 pm

It didn't work, what is happening is that when i unplug it from the computer and use my battery pack to power it, the sencer will be fine and work for about 30 seconds and then it will start to flash very rapidly and will not stop. It becomes unresponsive and wont stop unless i turn it off and back on or reset the board. How do i make it so the fingerprint sencer will just continue searching for fingerprints until the battery dies.
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Re: fingerprint sensor

by adafruit_support_bill on Thu Jan 03, 2013 5:46 pm

when i unplug it from the computer and use my battery pack to power it,

What happens if you don't unplug it? What battery pack are you using to power it?
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Re: fingerprint sensor

by bogeyer on Thu Jan 03, 2013 6:09 pm

If i dont unplug it and use the computer as a power source it works just fine and will work forever. The pack that came with the getting started kit
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Re: fingerprint sensor

by adafruit_support_bill on Thu Jan 03, 2013 6:16 pm

9v batteries have very limited current and a high internal resistance. What is happening is that the output voltage starts to drop, then the sensor stops functioning. You need a battery pack that can handle the combined load of the Arduino and fingerprint sensor. Something like a 6xAA battery holder should power it for a good while: http://www.adafruit.com/products/248
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Re: fingerprint sensor

by bogeyer on Thu Jan 03, 2013 7:41 pm

Thank you very much its running just fine now.
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