Update: we released a buzzer with a built-in driver circuit in August of 2022. The buzzer can be used with EZ F411 1-2S AIO.

You can buy it directly from our website.

In short, only the buzzer with built-in drive circuit can be used on this AIO flight controller. A common micro buzzer (that only has two legs and without pcb board) is incompatible with this 1S-2S AIO.

There're two solutions to add a buzzer on EZ. One solution is using a buzzer with a built-in driver circuit and then configuring the setting in betaflight. The other solution is a bit complicated, you need to add extra resistors to make the buzzer work on the EZ, if you like tweaking things and are familiar with circuit design, you can give this solution a go, we provide recommended circuit design below.

Solution One

Using a buzzer that comes with a built-in circuit driver


Here's the instruction of how to connect this buzzer with the fc and configure on Betaflight.

Choose an available port on the EZ AIO board to set up the buzzer, RX1 is mostly the available port on the EZ AIO, so we use this port as an example in this tutorial.

Step 1 Wiring diagram: 

FC RX1-- the Buzzer Signal Wire (Blue Wire), FC 5V–Buzzer 3V-5V ( Red Wire), FC GND–Buzzer GND (Black Wire)

Step2. In Betaflight,  Enter “resource” in the CLI to find out the pin number corresponding to the port.

For example, pin number on the EZ corresponding to RX1 is A10.

Step3 . Free the available port in the CLI and then set the corresponding pin as beeper, finally enter “save” in the CLI

For example, on the EZ AIO board, in the CLI, enter “resource serial_RX 1 NONE” , and then enter “resource beeper 1 A10”. Finally enter “save” and you are done.

After the setup, if the buzzer always keeps buzzing or can't be controlled, then please type the following command in CLI.
set beeper_inversion = OFF

FYI: If the buzzer could work properly, then you don't need to type the above command. 
(set beeper_inversion = OFF)

Solution TWo

The recommended circuit design is as follows.

300-1000Ohm resistor should work in this circuit. The transistor used in this circuit should be NPN type, you can use the common S8050 one. The buzzer signal interface can be connected to RX1 on the AIO flight controller and then in Betaflight, you should type the following commands in CLI to complete this setup. 

resource SERIAL_RX 1 NONE

resource BEEPER 1 NONE
resource BEEPER 1 A10