We use a Raspberry Pi, a Pi Pico, and a smartphone to communicate over Bluetooth.
Because the Raspberry Pi comes with both WiFi and Bluetooth, most programs choose to rely on WiFi, with Bluetooth being more of a wallflower. However, the Pi Pico mixes things up and makes Bluetooth a desirable option.
Bluetooth should be a familiar technology by way of your smartphone, and this topic has been investigated for the Raspberry Pi in a previous article , so I will be sticking to the bare minimum in terms of the basic technology in this article. The focus here is on various scenarios in which the Raspberry Pi, Pi Pico, and smartphones use Bluetooth to communicate. The Pico stands in for almost any microcontroller, as long as it supports serial communication.
The two basic prerequisites for Bluetooth communication between partners is pairing and trust between the parties. After you establish both once, the devices usually remember the trust relationship. After pairing, each of the two partners can establish a connection. The initiator is referred to as the host and the other partner as the device. However, each component can assume either role.
Use Express-Checkout link below to read the full article (PDF).