When constructing my dcc based train model, I looked for dcc decoder to pilot light (SMD 0402, or standard led), but had difficulty to program them for custom scenario (blinking, road works style, …).

This is a breadboard friendly breakout board for the Maxim MAX30105 reflectance, particle, and pulse ox sensor. This library should work with other MAX3010x sensors including the MAX30102, MAX30101, ...