Adafruit Trinket - Development Board

Even though you can program Trinket using the Arduino IDE, it's not a fully 100% Arduino-compatible. There are some things you trade off for such a small and low cost microcontroller!

• Trinket does not have a Serial port connection for debugging so the serial port monitor will not be able to send/receive data
• Some computers' USB v3 ports don't recognize the Trinket's bootloader. Simply use a USB v2 port or a USB hub in between

Here are some useful specifications!

• ATtiny85 on-board, 8K of flash, 512 byte of SRAM, 512 bytes of EEPROM
• Internal oscillator runs at 8MHz, but can be doubled in software for 16MHz
• USB bootloader with a nice LED indicator looks just like a USBtinyISP so you can program it with AVRdude (with a simple config modification) and/or the Arduino IDE (with a few simple config modifications)
• 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.
• We really worked hard on the bootloader process to make it rugged and foolproof, this board wont up and die on you in the middle of a project!
• ~5.25K bytes available for use (2.75K taken for the bootloader)
• Available in both 3V and 5V flavors
• On-board 3.3V or 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 #1 LED
• Reset button for entering the bootloader or restarting the program. No need to unplug/replug the board every time you want to reset or update!
• 5 GPIO - 2 shared with the USB interface. The 3 independent IO pins have 1 analog input and 2 PWM output as well. The 2 shared IO pins have 2 more analog inputs and one more PWM output.
• Hardware I2C / SPI capability for breakout & sensor interfacing.
• Works with many basic Arduino libraries including Adafruit Neopixel!
• Mounting holes! Yeah!
• Really really small