Datasheet
Hints for Arduino-compatibility
The Pro Trinket uses the Atmega328P chip, which is the same core chip in the Arduino UNO/Duemilanove/Mini/etc. It's
the 'classic' Arduino chip! So you'll be happy to hear that not only is Pro Trinket programmable using the Arduino IDE
as you already set up, but 99% of Arduino projects will work out of the box!
The Pro Trinket 5V runs at 16MHz, just like the Uno. The Pro Trinket 3V runs at 12MHz, which we suggest for 'power
users' who want a 3V Arduino-compatible and don't mind its a bit slower at 12MHz.
The only changes you may have to consider when adapting Arduino sketches are:
Pins #2 and #7 are not available
That means you do not get access to interrupt #0. Use interrupt #1 on pin #3 instead with attachInterrupt (1,
functionname, condition);
The onboard 3.3V or 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 3V Pro Trinket runs at 12MHz not 16MHz so its a bit slower.
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.
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