* **board** - breakout-specific pin identities
* **busio** - hardware-driven interfaces for I2C, SPI, UART
* **digitalio** - digital input/output pins, using pin identities from board+microcontroller packages
+* **keypad** - support for scanning keys and key matrices
* **microcontroller** - chip-specific pin identities
* **micropython** - MicroPython-specific module
* **neopixel_write** - low-level interface to NeoPixels
* **pulseio** - contains classes that provide access to basic pulse IO (PWM)
* **pwmio** - contains classes that provide access to basic pulse IO (PWM)
+* **rainbowio** - provides the colorwheel() function
+* **usb_hid** - act as a hid-device using usb_gadget kernel driver
For details, see the `Blinka API reference
<https://circuitpython.readthedocs.io/projects/blinka/en/latest/index.html>`_.