Oscilloscope

In this chapter we connect both active and passive buzzers to the Pico. We start with a simple button-controlled doorbell, improve the passive buzzer with bit-banging, and finally create a clean sweeping alert tone using the Pico’s PWM hardware. We also look at inductive-load protection and why a diode is essential.

In this chapter we create a reusable Pico.Analog package for PWM-based analogue output. We start with a classic breathing light, then move on to a flowing light bar. Along the way the MSO-5102B reveals the real behaviour of our code, and we discover (and fix) a subtle bug in the experimental RP2350 HAL.