Adafruit Pro Trinket 5V 16MHz

Here's some things you may have to consider when adapting Arduino sketches:

• Pins #2 and #7 are not available (they are exclusively for USB)
• The onboard 5V regulator can provide 150mA output, not 800mA out
• You cannot plug shields directly into the Pro Trinket
• There is no Serial-to-USB chip onboard. This is to keep the Pro Trinket small and inexpensive, you can use any FTDI cable to connect to the FTDI port for a Serial connection. The USB connection is for uploading new code only.
• The bootloader on the Pro Trinket use 4KB of FLASH so the maximum sketch size is 28,672 bytes. The bootloader does not affect RAM usage.

Here's some handy specifications:

• ATmega328P onboad chip in QFN package
• 16MHz clock rate, 28K FLASH available
• USB bootloader with a nice LED indicator looks just like a USBtinyISP so you can program it with AVRdude and/or the Arduino IDE (with a few simple config modifications).
• Also has headers for an FTDI port for reprogramming
• Micro-USB jack for power and/or USB uploading, you can put it in a box or tape it up and use any USB cable for when you want to reprogram.
• On-board 5.0V power regulator with 150mA output capability and ultra-low dropout. Up to 16V input, reverse-polarity protection, thermal and current-limit protection.
• Power with either USB or external output (such as a battery) - it'll automatically switch over
• On-board green power LED and red pin #13 LED
• Reset button for entering the bootloader or restarting the program.
• Works with 99% of existing Arduino sketches (anything that doesn't use more than 28K, and doesn't require pins #2 and #7)
• Mounting holes! Yeah!