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[on:]

I previously posted building a 12 LED light display where students could program their arduino and then move the chip on to the light display. I saw on the Marengo blog (http://www.marengo-ltd.com/blog/?p=150) a programmable circuit for the Arduino. I incorporated it into my light display design to hopefully produce a programmable light display. Hopefully we wreck less chips this way. I would greatly appreciate if someone could look at the Schematic and see if i missed anything.

Original post : http://arduino.cc/forum/index.php/topic,24497.0.html

Schmatic file: https://docs.google.com/leaf?id=0B4G1hbUR7lo-MWUxOWU3ZWEtYTAyZS00NWIyLTk0ODEtZTg2NDY4NjA0MjFm&hl=en_US

[Reply #1 on:]

I would add an extra decoupling capacitor of 0.1uF on the output of the regulator across C2. As C2 is a large electrolytic it won't be able to cope with the higher frequency stuff.
Also a 0.1uF cap on pin 21 to ground.

[Reply #2 on:]

Ok, i made the 2 changes. the link attached is the revised schematic.

https://docs.google.com/leaf?id=0B4G1hbUR7lo-NjQwMDcxNzctMWYzNy00MmQzLWI3NDEtZDQ2NzA1ZDNhODI5&hl=en_US&authkey=CLiC8bwF