USB

Introduction

The Omega2 features a single USB 2.0 host.

Hardware

One USB 2.0 host controller is available on dedicated pins.

A 5V power source needs to be supplied to the USB client device to properly operate.

The USB pins are highlighted on the Omega2/2S diagrams below.

Omega2

Omega2S

info

See the Omega2S hardware design guide for more information and recommendations on designing boards with USB.

USB storage

Omega2 firmware includes the kernel modules required for external USB storage - including support for a variety of file systems.

Mounting the file system

To mount the file system, plug in a USB drive and you’ll see a message like:

[ 1704.267974] usb 1-1: new high-speed USB device number 2 using ehci-platform  [ 1704.479893] 
usb-storage 1-1:1.0: USB Mass Storage device detected  [ 1704.502029] 
scsi host0: usb-storage 1-1:1.0  [ 1705.530163] 
scsi0:0:0:0: Direct-Access Generic Flash Disk 8.07 PQ: 0 ANSI: 4  [ 1705.549739] 
sd 0:0:0:0: [sda] 15728640 512-byte logical blocks: (8.05 GB/7.50 GiB)  [ 1705.559385] 
sd 0:0:0:0: [sda] Write Protect is off  [ 1705.564277] 
sd 0:0:0:0: [sda] Mode Sense: 23 00 00 00  [ 1705.565444] 
sd 0:0:0:0: [sda] Write cache: disabled, read cache: enabled, doesn't support DPO or FUA  [ 1705.583833]  
sda: sda1  [ 1705.596761] 
sd 0:0:0:0: [sda] Attached SCSI removable disk

Note on the second last line that the new device is called sda1.

The file system from the USB drive will be automatically mounted to the /mnt/ directory, with the name of the device as the full path, so /mnt/sda1 in this case.

root@Omega-F19D:/_# ls -l /mnt/sda1_
drwxrwxrwx    2 root     root          4096 Jun  1  2018 System Volume Information
-rwxrwxrwx    1 root     root             0 Jun 17  2021 omega2p-v0.3.3-b251.bin

Unmounting the file system

Before you remove the USB drive, you must unmount the file system.

umount /mnt/sda1