The Adafruit Trinkey is a tiny USB key format microcontroller with four Neopixels and an M0 processor.
I bought mine from Pimoroni.
When plugged into the USB port of my Debian laptop, it failed to register. I thought it might be an issue with connecting to an elderly ex-Windows laptop. So I tried it on a Windows laptop. Still it did not register. The Neopixels worked, and the touch sensors started and stopped the display.
However, when set to Boot Mode (double press on the reboot button) it registered as a USB device.
I then downloaded the latest version of CircuitPython from https://circuitpython.org/board/neopixel_trinkey_m0/
This was then copied to the device which then causes the device to restart. The device now appeared as a USB memory device.
This was then copied to the device which then causes the device to restart. The device now appeared as a USB memory device.
Programming
CircuitPython devices are simple to program, appearing as a USB memory device. Saving a new file to the device causes it to restart. Generally the file code.py is executed on starting.
Adafruit's recommendation is to use the Mu editor. This writes directly to the CircuitPython device. It does however mean you need to be particularly careful that you have a copy of the code somewhere.
To make my life easier, I put together a simple Visual Studio program to copy specific code.py files from specific folders. I then edited the code using Visual Studio Code.
Example code
The example code is derived from the code from the Neo Trinkey Zoom Short Cut project (see references)
import time
import board
import neopixel
# setup for onboard neopixels
pixel_pin = board.NEOPIXEL
num_pixels = 4
pixels = neopixel.NeoPixel(pixel_pin, num_pixels, brightness=0.05, auto_write=False)
def wheel(pos):
# Input a value 0 to 255 to get a color value.
# The colours are a transition r - g - b - back to r.
if pos < 0 or pos > 255:
return (0, 0, 0)
if pos < 85:
return (255 - pos * 3, pos * 3, 0)
if pos < 170:
pos -= 85
return (0, 255 - pos * 3, pos * 3)
pos -= 170
return (pos * 3, 0, 255 - pos * 3)
def rainbow_cycle(wait):
for j in range(255):
for i in range(num_pixels):
rc_index = (i * 256 // num_pixels) + j
pixels[i] = wheel(rc_index & 255)
pixels.show()
time.sleep(wait)
while True:
rainbow_cycle(0.001)
References
https://www.adafruit.com/product/4870
https://circuitpython.org/board/neopixel_trinkey_m0/
