put a .1mF across the chip, tie reset to Vcc

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For the uninitiated, like me, these two points
cannot be be reinforced enough!

It's simply amazing what problems are solved
(due to unclean power) by using a 0.1mF cap
across Vcc and ground near the chip.
I amazed myself anyway... The noise from the
chip itself is enough to call for this filter
cap, forget about unclean supply! Your own
chip will defy you -- suck the noise out for
only 0.1mF, what a deal!

And if you haven't heard it already - put a
pullup resistor on RESET if you don't have
any other electronics controlling the reset pin.
Better yet - Atmel says it's OK to tie reset
DIRECTLY to Vcc, can't hurt.
(I found that probing the reset pin with o'scope
was enough to cause reset when using a 10K pullup,
but no way does it reset when tied straight to Vcc.)
Without *any* tie up, using the I/O line NEXT TO
the reset pin can be enough to trigger a reset when
transitioning that I/O from hi to lo. It's true!

Just my two bits (semi-nibble?) worth.
Scott

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I think the purpose of the resistor there is for power supplies that may be spikey (sp?), or soft start. That resistor in conjunction with some internal capacitance holds the chip in reset until things stabilize on Vcc.

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