Things go a different route as soon as you’re trying to communicate with other electronic gadgets that uses Bluetooth modules connected to the serial port of the Raspberry Pi.
These modules are very cheap to buy, the actual module is the green board that sits on the breakout board in my model. The pure HC-05 will only work on 3.3V levels, not with 5V-TTL-levels. So one would need level shifters (again).
In this section, we will communicate the Raspberry Pi Zero to the Bluetooth module, and connect the pins TX and RX of the Raspberry Pi.
First, we need to configure the file of the system to make some changes in order to activate the communication of the Raspberry Pi Zero TX and RX: