USB

The Universal Serial Bus (USB) can be utilized for many functions on the development kit, including external media. The phyCORE-AM62x development kit provides two USB 2.0 Dual-Role Devices (DRD) subsystems via the three USB connectors (X43, X36, and X34). This guide will show you how to use the USB Host capabilities featured on the phyCORE-AM62x development kit. To learn more information about the phyCORE-AM62x USB interface, please see section 7.6 in the Hardware Manual.

The USB0 interface is brought out as a type-C connector (X34). The USB1 interface uses a USB HUB to split the bus to 3x locations.

USB Locations
Type	Qty	Header Location	Speed	Bus
USB A Double Stacked	2	X43	2.10	001
Mini PCIe	1	X36	2.10	001
USB C	1	X34	2.10	003

Requirements

USB Storage Device

Verifying USB Interface

With the phyCORE-AM62x development kit booted into Linux, verify that there are 2 USB devices.

Target (Linux)

lsusb

Expected Output

root@phyboard-lyra-am62xx-3:~# lsusb
Bus 001 Device 002: ID 0424:2514
Bus 001 Device 001: ID 1d6b:0002 Linux 6.1.33-bsp-yocto-ampliphy-am62x-pd23.2-rc1 xhci-hcd xHCI Host Controller

Insert a USB device into either x43 (Double stack USB-A port) or x34 (USB-C). This guide demonstrates the USB-A bottom port.

Expected Output

root@phyboard-lyra-am62xx-3:~# [ 2764.219680] usb 1-1.2: new high-speed USB device number 3 using xhci-hcd
[ 2764.325351] usb 1-1.2: New USB device found, idVendor=0781, idProduct=5591, bcdDevice= 1.00
[ 2764.333870] usb 1-1.2: New USB device strings: Mfr=1, Product=2, SerialNumber=3
[ 2764.341297] usb 1-1.2: Product:  SanDisk 3.2Gen1
[ 2764.346029] usb 1-1.2: Manufacturer:  USB
[ 2764.350144] usb 1-1.2: SerialNumber: 0401a83fbd697e437712b826697973aaaf57d1c75e9691ad879dfe7934b8a81bea020000000000000000000037ac13c5ff935d18915581076e2cc649
[ 2764.411781] usb-storage 1-1.2:1.0: USB Mass Storage device detected
[ 2764.418828] scsi host0: usb-storage 1-1.2:1.0
[ 2764.424110] usbcore: registered new interface driver usb-storage
[ 2765.448829] scsi 0:0:0:0: Direct-Access      USB      SanDisk 3.2Gen1 1.00 PQ: 0 ANSI: 6
[ 2765.463168] sd 0:0:0:0: [sda] 30031872 512-byte logical blocks: (15.4 GB/14.3 GiB)
[ 2765.481193] sd 0:0:0:0: [sda] Write Protect is off
[ 2765.486641] sd 0:0:0:0: [sda] Write cache: disabled, read cache: enabled, doesn't support DPO or FUA
[ 2765.504741] sd 0:0:0:0: [sda] Attached SCSI removable disk

Verify that the USB was properly recongnized by development kit.

Target (Linux)

lsusb

Expected Output

root@phyboard-lyra-am62xx-3:~# lsusb
Bus 001 Device 003: ID 0781:5591  USB  SanDisk 3.2Gen1
Bus 001 Device 002: ID 0424:2514
Bus 001 Device 001: ID 1d6b:0002 Linux 6.1.33-bsp-yocto-ampliphy-am62x-pd23.2-rc1 xhci-hcd xHCI Host Controller

To list more information about the USB device and buses on the development kit use the following command.

This command will output a good chunk of information. This guide will only show a snippet of the expected output for the USB drive that was just connected.
Target (Linux)
```
lsusb -v -s 001:003
```
Note

“001” refers to bus 001 and “003” refers to the device number, both of these can be found in the lsusb command.

Expected Output for Example USB Drive

Bus 001 Device 003: ID 0781:5591  USB  SanDisk 3.2Gen1
Device Descriptor:
  bLength                18
  bDescriptorType         1
  bcdUSB               2.10
  bDeviceClass            0
  bDeviceSubClass         0
  bDeviceProtocol         0
  bMaxPacketSize0        64
  idVendor           0x0781
  idProduct          0x5591
  bcdDevice            1.00
  iManufacturer           1  USB
  iProduct                2  SanDisk 3.2Gen1
  iSerial                 3 0401a83fbd697e437712b826697973aaaf57d1c75e9691ad879dfe7934b8a81bea020000000000000000000037ac13c5ff935d18915581076e2cc649
  bNumConfigurations      1
  Configuration Descriptor:
    bLength                 9
    bDescriptorType         2
    wTotalLength       0x0020
    bNumInterfaces          1
    bConfigurationValue     1
    iConfiguration          0
    bmAttributes         0x80
    ...

The speed of the USB device can be determined with either the lsusb -v from above or by reading the device’s “speed”
Target (Linux)
```
cat /sys/bus/usb/devices/1-1.2/speed
```
Expected Output
```
root@phyboard-lyra-am62xx-3:~# cat /sys/bus/usb/devices/1-1.2/speed
480
```
Note

USB2.0 has transmission speeds up to 480Mbit/s, also known as “full speed”.

Mounting USB Stroage Devices

Verify that a device directory was established for the USB drive.

Run the following command to confirm the USB device name.
Target (Linux)
```
ls /dev/sd*
```
Expected Output
```
root@phyboard-lyra-am62xx-3:~# ls /dev/sd*
/dev/sda
```
Remove the USB drive and re-insert it.

The output log that appears when connecting the USB device will indicate the devices name.

Expected Output

 root@phyboard-lyra-am62xx-3:~# [ 3383.212335] usb 1-1.2: USB disconnect, device number 3
 [ 3384.927924] usb 1-1.2: new high-speed USB device number 4 using xhci-hcd
 [ 3385.037370] usb 1-1.2: New USB device found, idVendor=0781, idProduct=5591, bcdDevice= 1.00
 [ 3385.045888] usb 1-1.2: New USB device strings: Mfr=1, Product=2, SerialNumber=3
 [ 3385.053314] usb 1-1.2: Product:  SanDisk 3.2Gen1
 [ 3385.058057] usb 1-1.2: Manufacturer:  USB
 [ 3385.062170] usb 1-1.2: SerialNumber: 0401a83fbd697e437712b826697973aaaf57d1c75e9691ad879dfe7934b8a81bea020000000000000000000037ac13c5ff935d18915581076e2cc649
 [ 3385.081737] usb-storage 1-1.2:1.0: USB Mass Storage device detected
 [ 3385.091833] scsi host0: usb-storage 1-1.2:1.0
 [ 3386.113594] scsi 0:0:0:0: Direct-Access      USB      SanDisk 3.2Gen1 1.00 PQ: 0 ANSI: 6
 [ 3386.123449] sd 0:0:0:0: [sda] 30031872 512-byte logical blocks: (15.4 GB/14.3 GiB)
 [ 3386.135612] sd 0:0:0:0: [sda] Write Protect is off
 [ 3386.141430] sd 0:0:0:0: [sda] Write cache: disabled, read cache: enabled, doesn't support DPO or FUA
 [ 3386.161894] sd 0:0:0:0: [sda] Attached SCSI removable disk

Note

In this example the device name for the USB drive is “sda”.

Make a directory for mounting the USB device.
Target (Linux)
```
 mkdir ~/usb_sda
```
Format file type.
Target (Linux)
```
 mkfs.vfat /dev/sda
```
Mount the USB device to the directory.
Target (Linux)
```
mount /dev/sda ~/usb_sda/
```
See what media is on the USB drive.
Target (Linux)
```
 ls ~/usb_sda/
```

Write to the USB Host Device

Generate a random 10 MB file to test transferring data from the storage device.

Target (Linux)

dd if=/dev/urandom of=test.file count=10 bs=1M

Expected Output

root@phyboard-lyra-am62xx-3:~# dd if=/dev/urandom of=test.file count=10 bs=1M
10+0 records in
10+0 records out
10485760 bytes (10 MB, 10 MiB) copied, 0.161874 s, 64.8 MB/s

Copy the file to your storage device.

Target (Linux)

cp test.file ~/usb_sda/ && sync

Read from the USB Host Device

Copy the test file we previously created during the write process back to the host:
Target (Linux)
```
cp ~/usb_sda/test.file readback-usb.file && sync
```

We can double check that the file was successfully copied to and from the USB device by checking the md5sum of the file:

Target (Linux)

md5sum test.file readback-usb.file

Expected Output

root@phyboard-lyra-am62xx-3:~# md5sum test.file readback-usb.file
d3aa3ee1db746d6f7fb66c9b42f4ea6b  test.file
d3aa3ee1db746d6f7fb66c9b42f4ea6b  readback-usb.file

Unmounting the Drive

Warning

Make sure the drive is unmounted prior to physically disconnecting the device. Failure to do so may result in loss of data and corruption of files

Target (Linux)

umount ~/usb_sda/
umount /dev/sda