Datasheet

As part of the 'Express' series of boards, this ItsyBitsy is

designed for use with CircuitPython.

To make that easy, we have added two extra parts: a

mini DotStar (RGB LED) and a 2 MB QSPI (Quad SPI)

Flash chip.

The DotStar is connected to pin #6 (clock) and #8 (data)

in Arduino, so just use our DotStar

library (https://adafru.it/zbD) and set it up as a single-LED

strand on pins 6 & 8. The DotStar is powered by the

3.3V power supply but that hasn't shown to make a big

difference in brightness or color.

The QSPI Flash is connected to 6 pins that are not brought out on the GPIO pads. QSPI is neat because it allows you to

have 4 data in/out lines instead of just SPI's single line in and single line out. This means that QSPI is

at least

4 times

faster. But in reality is at least 10x faster because you can clock the QSPI peripheral much faster than a plain SPI

peripheral

We have an Arduino library here which provides QSPI interfacing for Arduino (https://adafru.it/wbt). In CircuitPython, the

QSPI flash is used natively by the interpreter and is read-only to user code, instead the Flash just shows up as the

writable disk drive!