ESP32 Forum

Posted: **Thu Dec 19, 2024 2:20 pm**

MCU: ESP32-WROOM-32E
Hello,
My goal is to have two ESP32s communicate via Bluetooth. I am using this master and slave code from GitHub to allow communication, but the two MCUs never connect.
To determine if the devices could be detected, I ran the bt_classic_device_discovery built-in example. When running it on the ESP32 that connects to COM5, the program runs successfully and I am able to detect my ESP32_SLAVE device. However, when running the program on the ESP32 connected to COM3, I get the following error:
#3error Serial Bluetooth not available or not enabled. It is only available for the ESP32 chip.
Both devices have Bluetooth enabled because when either one connects to COM5, I do not get the above error, but when they connect to COM3, I do.
I was wondering what steps I should take to debug.
Thanks.

Posted: **Sat Dec 21, 2024 1:52 pm**

only the ESP32 supports Bluetooth Classic 4.2 see https://gist.github.com/sekcompsci/2bf3 ... 4fa819f421

have a look at BLE - File>Examples>BLE>UART

probably simpler to use WiFI e.g. ESP-NOW https://randomnerdtutorials.com/esp-now ... duino-ide/

Posted: **Sat Dec 21, 2024 5:46 pm**

Set your core debug level to verbose. In the output, you should have a section for chip info. Make sure it shows Classic BT. Mine looks like this for a Pico-v3 board. Communication over BLE is preferable to classic (due to the LE part).

Code: Select all

07:44:30.078 -> Chip Info:
07:44:30.078 -> ------------------------------------------
07:44:30.078 ->   Model             : ESP32
07:44:30.078 ->   Package           : PICO-V3-02
07:44:30.112 ->   Revision          : 3.00
07:44:30.112 ->   Cores             : 2
07:44:30.112 ->   CPU Frequency     : 240 MHz
07:44:30.112 ->   XTAL Frequency    : 40 MHz
07:44:30.112 ->   Features Bitfield : 0x000000b3
07:44:30.112 ->   Embedded Flash    : Yes
07:44:30.145 ->   Embedded PSRAM    : Yes
07:44:30.145 ->   2.4GHz WiFi       : Yes
07:44:30.145 ->   Classic BT        : Yes
07:44:30.145 ->   BT Low Energy     : Yes
07:44:30.145 ->   IEEE 802.15.4     : No

ESP32 Forum

Error: Serial Bluetooth not available or not enabled. It is only available for the ESP32 chip.

Error: Serial Bluetooth not available or not enabled. It is only available for the ESP32 chip.

Re: Error: Serial Bluetooth not available or not enabled. It is only available for the ESP32 chip.

Re: Error: Serial Bluetooth not available or not enabled. It is only available for the ESP32 chip.