My Opinion:
Barebone is simply not for those without sufficient experience with the non-bare product(s). Even for us old timers, it can be stressful getting such projects to perform.
There is simply not enough $aving$ to warrant going this route. I have 3 such projects on my bench right now - but, I'm designing small singke-purpose chips to frontend signal processing for a downstream Mega2560.
ADDED: 20130613 ...
Extreme bareboard (EBB) No Crystal... just chip.
How does this no-crystal thing work? Essentially, we are simply going to run the 16MHz Atmel328P at 8MHz-ish (RC oscillators are not as accurate as crystals) and the Arduino programming environment will set all the timing constants at compile time. This means that such things as tone() will continue to work at the correct frequency as with functions such as millis(). To make this magic happen, we need to provide the Arduino environment with some information about our new hardware configuration. Such information is provide to the client Arduino software on your PC/Mac/Linux box via a file named boards.txt. The following article explains how to install the file:
http://arduino.cc/en/Tutorial/ArduinoToBreadboard please refer to the section titled: Minimal Circuit (Eliminating the External Clock) The screen-capture of the settings used by the 8MHz RC fuse configuration is shown in the second graphic.The no crystal approach may be a great way to save a few cents on your next barebones project or lower the power requirements for battery operated projects. Most things will work OK with the lower frequency; however, please remember that timing-critical stuff such as serial communications to the PC or other devices (say, reading a GPS) are likely NOT the proper place to save the price of a crystal. That being said, you may still wish to consider the lowering of the standard 16MHz frequency to a lower crystal frequency of 8MHz to lower the power requirements.
- Ray
