"A relay card used with a Raspberry Pi Pico extends its functionality by enabling the control of high-power electrical devices that require voltages or currents beyond what the Pico's GPIO pins can directly handle. Typically, relay cards feature multiple relays, each capable of switching circuits on or off in response to signals from the Pico. These relays act as electrically controlled switches, isolating the low-voltage control signals from the high-power circuits they control.
The Raspberry Pi Pico communicates with the relay card through its GPIO pins, sending signals that energize or de-energize individual relays. This capability allows the Pico to control a wide range of external dev...