Trinket is a tiny microcontroller board, built around Atmel ATtiny85 IC, a little chip with a lot of power. Its a low cost, small size board, perfect for when you don't want to use your expensive development board,it's lowest-cost arduino-IDE programmable board.Its comes with 8K flash memory and has 5 GPIO pins, including analog inputs and PWM outputs. Its comes with USB bootloader, so you can plug it into any computer and reprogram it over a USB port just like an Arduino.
This is the 5V Trinket. There are two versions of the Trinket boards available , One is 3V and one is 5V. Both work the same, but have different operating logic voltages.The 3V version should only run at 8 MHz, whereas the 5V version can run at 8 MHz or at 16MHz by setting the software-set clock frequency. Even though you can program Trinket using the Arduino IDE, it's not a fully 100% Arduino-compatible.
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