#11 - GPIO #11, can do PWM output.
#12 - GPIO #12, also analog input A11
#13 - GPIO #13, can do PWM output and is connected to the red LED next to the Reset button
Along the left edge
A0 thru A5 - These are each analog input as well as digital I/O pins.
SCK/MOSI/MISO - These are the hardware SPI pins, you can use them as everyday GPIO pins but recommend
keeping them free as they are best used for hardware SPI connections for high speed. Also used to reprogram
the chip with an AVR programmer if you need.
Along the short edge:
#4 - GPIO #4, also analog input A6
#6 - GPIO #6, can also do PWM output and analog input A7
#8 - GPIO #8, also analog input A8
Other Pins!
RST - this is the Reset pin, tie to ground to manually reset the AVR, as well as launch the bootloader manually
ARef - the analog reference pin. Normally the reference voltage is the same as the chip logic voltage (3.3V or
5V) but if you need an alternative analog reference, connect it to this pin and select the external AREF in your
firmware. Don't set it higher than the logic level of the Itsy!
© Adafruit Industries
https://learn.adafruit.com/introducting-itsy-bitsy-32u4
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