AVR-Chat

At 09:52 AM 23/10/2007, you wrote:
>I need for this thing to start up whenever the locomotive sees
>power

Enable the Brown Out Detector, this will give you reliable reset
at power up.

The point I'm trying to make is that, if you have a track running
from the reset line, say to the ISP connector, then you have a small
antenna connected to the reset line. With a high resistance in the reset
line like the internal pull up, one is more likely to pick up rubbish
that COULD give you spurious resets. A cap on the reset line will help
with this as well as giving you another reset at power up.

However you SHOULD use the internal BOD at least for better reliability.

I'm fortunate enough that my projects have never been that packed or
price sensitive that I could not put a cap and resistor in the reset line.

Try it without see what happens, I may just be a panic merchant :-)


Regards

John Samperi

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Ampertronics Pty. Ltd.
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Email: john@ampertronics.com.au
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