.. include:: ../substitutions.rst
.. include:: stdout.rst

USB 2.0
=======

The i.MX RT1170 processor includes two USB 2.0 controllers (``usb1`` and ``usb2``), both enabled in the current |release-name| release. ``usb1`` (OTG1) is routed to connector X16 on the |product-cb| carrier board and serves as the |product| development kit's USB-OTG Serial Downloader port, used for flashing firmware as described in the Installing the Firmware guide. ``usb2`` (OTG2) is routed to connector X17 on the |product-cb| carrier board for application use.

.. image:: ../../images/phycore-rt1170/interfaceguides/usb-callout.webp
   :width: 600px

For detailed hardware-level information, refer to the *7.7 USB* chapter in the |hw-manual-link|.

Build Usage
-----------

.. note::

   The pre-built |release-name| sample application includes a USB Mass Storage Class (MSC) device that starts automatically at boot. It exposes an SD card inserted into the |product-cb| carrier board's SD card slot as a USB disk to a connected host PC.

   The sample's board overlay (``app/rt1170/boards/phyboard_atlas_mimxrt1176_cm7.overlay``) redirects the ``zephyr_udc0`` USB device controller alias to ``&usb2``, which is why the MSC device enumerates on connector X17 (OTG2) rather than X16 (OTG1).

   To use OTG1 (X16) instead, delete the following lines from the overlay and rebuild the application:

   .. code-block:: none

      /delete-node/ &zephyr_udc0;

      zephyr_udc0: &usb2 {
         status = "okay";
      };

* Insert an SD card into the |product-cb| carrier board's SD card slot.

* Connect a USB cable between your host PC and connector X17 on the |product-cb| carrier board.

* The SD card will enumerate on the host PC as a removable USB Mass Storage disk.

Once connected, the target console logs the MSC device coming up:

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

   [00:00:08.500,000] <inf> usbd_msc: Enable
   [00:00:08.501,000] <inf> usbd_msc: Bulk-Only Mass Storage Reset

On the host PC, the sample exposes two SCSI disks: a small built-in RAMDisk and the inserted SD card. Check ``dmesg`` to confirm both were detected:

.. code-block:: console
   :caption: Host (Linux)

   dmesg

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

   usb 1-9.1.1: new high-speed USB device number 51 using xhci_hcd
   usb 1-9.1.1: New USB device found, idVendor=2fe3, idProduct=cafe, bcdDevice= 4.04
   usb 1-9.1.1: New USB device strings: Mfr=1, Product=2, SerialNumber=3
   usb 1-9.1.1: Product: USBD MSC sample
   usb 1-9.1.1: Manufacturer: Zephyr Project
   usb 1-9.1.1: SerialNumber: 0428180E8295D12F
   usb-storage 1-9.1.1:1.0: USB Mass Storage device detected
   scsi host0: usb-storage 1-9.1.1:1.0
   scsi 0:0:0:0: Direct-Access     Zephyr   RAMDisk          0.00 PQ: 0 ANSI: 4
   scsi 0:0:0:1: Direct-Access     Zephyr   SD               0.00 PQ: 0 ANSI: 4
   scsi 0:0:0:0: Attached scsi generic sg0 type 0
   scsi 0:0:0:1: Attached scsi generic sg1 type 0
   sd 0:0:0:0: [sda] 192 512-byte logical blocks: (98.3 kB/96.0 KiB)
   sd 0:0:0:0: [sda] Write Protect is off
   sd 0:0:0:0: [sda] Mode Sense: 03 00 00 00
   sd 0:0:0:1: [sdb] 15859712 512-byte logical blocks: (8.12 GB/7.56 GiB)
   sd 0:0:0:0: [sda] No Caching mode page found
   sd 0:0:0:0: [sda] Assuming drive cache: write through
   sd 0:0:0:1: [sdb] Write Protect is off
   sd 0:0:0:1: [sdb] Mode Sense: 03 00 00 00
   sd 0:0:0:1: [sdb] No Caching mode page found
   sd 0:0:0:1: [sdb] Assuming drive cache: write through
   sd 0:0:0:0: [sda] Attached SCSI removable disk
    sdb: sdb1
   sd 0:0:0:1: [sdb] Attached SCSI removable disk

In this example, ``sda`` is the sample's built-in RAMDisk and ``sdb`` (with partition ``sdb1``) is the inserted SD card.

.. include:: ../../common/support-disclaimer-us.rst