Bluetooth
===========

This guide will show you how to connect to the phyCORE-i.MX8X development kit using the on-board `Sterling-LWB WiFi/Bluetooth module <https://www.lairdconnect.com/wireless-modules/wifi-modules-bluetooth/sterling-lwb-24-ghz-wifi-4-bt-51-module>`_.

.. note:: The Wifi/BT module can not be used at the same time as the SD card reader so the user must boot from eMMC.

          Please refer to our :ref:`flasheMMC-8x` guide for more information.


.. image:: ../../images/phycore-imx8x/pcm-065_bt-callout.webp
    :width: 800px
    :alt: Bluetooth Callout

Requirements
-------------

* Bluetooth capable device to test with

Setting Up Hardware
--------------------

* With the development kit powered off make sure the necessary switches are configured correctly.

  #. Set S10 to the eMMC boot configuration. Refer to the Boot Switches configuration page for more information.

     .. image:: ../../images/phycore-imx8x/pcm-065_emmc_boot-switches.webp
         :width: 500px

  #. Set S7 to the ON position.

* Power on the board and stop in U-Boot.

* Make sure your environment variables are set correctly and boot into Linux.

  .. code-block:: none
    :caption: Target (U-Boot)

    setenv mmcdev 0
    setenv mmcroot "/dev/mmcblk0p2 rootwait rw"
    setenv overlay_files phytec-imx8qxp-bt.dtbo
    boot

Connecting A Bluetooth Device
-------------------------------

* After logging into Linux, run the brcm_patchram_plus utility which may take a second or two. This utility patches the firmware to the radio.

  .. code-block:: none
    :caption: Target (Linux)

    brcm_patchram_plus --patchram /lib/firmware/brcm/BCM43430A1.hcd --enable_hci --no2bytes --tosleep 1000 /dev/ttyLP1 &

 .. code-block:: none
   :caption: Expected Output

   [   38.357433] Bluetooth: HCI UART driver ver 2.3
   [   38.362003] Bluetooth: HCI UART protocol H4 registered
   [   38.367189] Bluetooth: HCI UART protocol BCSP registered
   [   38.372729] Bluetooth: HCI UART protocol LL registered
   [   38.377926] Bluetooth: HCI UART protocol ATH3K registered
   [   38.384044] Bluetooth: HCI UART protocol Broadcom registered
   [   38.389865] Bluetooth: HCI UART protocol QCA registered
   Done setting line discpline

* Check that the bluetooth module was properly configured using the "hciconfig" command.

  .. code-block:: none
    :caption: Target (Linux)

    hciconfig

  .. code-block:: none
    :caption: Expected Output

    hci0:   Type: Primary  Bus: UART
            BD Address: 00:25:CA:35:52:0C  ACL MTU: 1021:8  SCO MTU: 64:1
            DOWN
            RX bytes:675 acl:0 sco:0 events:35 errors:0
            TX bytes:427 acl:0 sco:0 commands:35 errors:0

* Bring the Bluetooth interface up.

  .. code-block:: none
    :caption: Target (Linux)

    rfkill unblock bluetooth
    hciconfig hci0 up

* Run "hcitool lescan" in Linux to scan for your external device.

  .. code-block:: none
      :caption: Target (Linux)

       hcitool lescan

  .. code-block:: none
    :caption: Expected Output

    LE Scan ...
    18:EE:69:04:69:72 (unknown)
    0B:E4:8A:B0:80:78 (unknown)
    11:4F:37:EB:2A:6C (unknown)
    5A:B0:B7:F2:5B:27 (unknown)
    31:BC:21:21:9C:5F Raycon E55 Earbuds
    31:BC:21:21:9C:5F (unknown)
    64:E7:A7:29:11:AA (unknown)
    66:2C:40:EC:77:C9 (unknown)
    7F:3B:C9:53:54:E4 (unknown)
    7F:3B:C9:53:54:E4 (unknown)
    41:CC:AD:C6:0F:C2 (unknown)
    57:80:3F:07:D6:B7 (unknown)
    64:E7:A7:29:11:AA (unknown)
    2A:B2:24:F3:FB:EB (unknown)
    18:EE:69:04:69:72 (unknown)