Battery backup for GPS shield

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wesg
 
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Battery backup for GPS shield

Post by wesg »

I just bought the GPS shield and receiver, with the plan of putting it in my car to do a little travel visualization. The last bit of the tutorial states that the Arduino and shield shouldn't be powered off without pulling the TX wire first. There is also a mention about a battery backup on the shield, so does that mean with the battery I can pull the power plug so that the buffer is written before shutting down? It would be great if there was something I could do to avoid pulling the TX wire each time.

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adafruit_support_bill
 
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Re: Battery backup for GPS shield

Post by adafruit_support_bill »

The battery backup is for the GPS module. It will not keep the SD card interface powered through the write cycle.

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wesg
 
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Re: Battery backup for GPS shield

Post by wesg »

Is there anything I can do to create a write buffer for when the power goes off?

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adafruit_support_bill
 
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Re: Battery backup for GPS shield

Post by adafruit_support_bill »

You could add a "shutdown" button to stop the sketch (and maybe light a led to indicate that it is stopped) and then turn off the power.

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wesg
 
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Re: Battery backup for GPS shield

Post by wesg »

That might work... what about a battery backup circuit that maybe uses a cap to provide power for a second or less? Is that a fairly simple circuit?

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Re: Battery backup for GPS shield

Post by adafruit_support_bill »

That could work. But you need to make sure that the sketch is stopped before the cap runs out.

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Re: Battery backup for GPS shield

Post by wesg »

Yep, that was my plan. I figure I'll try to use a pull-up resistor on one of the input pins to check for proper power, and enter a blank loop once the voltage drops. Thanks for your help, Adafruit support!

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