i have a project that i am working on (simple 3W RGB LED mood light driven with a ULN2003 darlington transistor array). i have the source code in my uno board. the question i have is the uno has a 16 mhz crystal for the clock signal. without the crystal it run at 8mhz internally. is there anything in programming that has to change to work the circuit. i am wanting to take out the atmega 328 chip and use it without the arduino uno board. all advise is appreciate. i have searched over the internet and forum but cant find the answer im looking for.
What you wish to do is possible but there are chip internal fuse settings changes needed to converting from external 16Mhz to internal 8Mhz. It's much easier to just get a 16Mhz three terminal resonator to use in your standalone operation. That will save you a lot of fustration, trust me. You just ground the center pin and wire the outside pins to pins 9 and 10 of the 328 chip, no padding caps required. This will allow you to move the 328 chip back and forth between your arduino board and your standalone setup.http://www.sparkfun.com/products/9420