Category Archives: SATADOCK-USB2-C1

Raspberry Pi and Plugable Devices

We recently received a Raspberry Pi at the Plugable offices and we have been using it to test how our various devices interact with it. The Raspberry Pi has 2 USB 2.0 Ports, and no USB 3.0 ports, so our testing was focused on USB 2.0 devices and a couple USB 3.0 storage devices.

All of these tests were carried out on a Raspberry Pi Model B using the latest version of Raspbian wheezy. Here’s a video of the full setup, followed by a bunch of detail about our tests:

Hubs

  • Plugable USB 2.0 7 Port Hub with 3A Power Adapter – No Issues
  • Plugable USB 2.0 4 Port Hub with 2.5A Power Adapter – No issues
  • Plugable USB 2.0 10 Port Hub with 2.5A Power Adapter – Causes the Raspberry Pi to reboot upon connection, because it supplements the 2.5A wall power with 500mA from the upstream port. This is too much for the Pi., but just at the moment it is plugged in. If you plug the 10 port hub in when the Pi is powered down, you can boot into the Pi and all will be well. But since there are better options (like the 7 port hub above), we don’t recommend our 10 port hub with the Pi.
  • USB2-2PORT – Causes the Raspberry Pi to reboot upon connection. This is simply because this is an unpowered hub. Only hubs with their own power adapter should be used with the Pi.
  • USB3-HUB7-81x – USB HID devices(Mice, Keyboards) are known not to work with this hub on the Raspberry Pi.
  • USB3-HUB81x4  - USB HID devices(Mice, Keyboards) are known not to work with this hub on the Raspberry Pi.
  • USB2-SWITCH2 – No issues

Other Devices

The common pattern with all devices is you must have one of the powered usb hubs above and connect the device through that. If you don’t, the Pi won’t be able to handle the power draw, and it will drop voltage and reset.

Ethernet:

Storage:

Plugable USB2-Micro-200X USB Microscope:

  • On a Raspberry Pi running Raspbian we have test our Microscope connected through a powered USB hub to work with GTK+ UVC Viewer by using the following terminal commands:

    “sudo apt-get install guvcview”
    “guvcview”

Let us know if there are any other Plugable products you’d like us to test, or if you have any questions at all – we’d be happy to help. Thanks for your support of Plugable products!

Where to Buy
[usb2-hub-ag7-post]

Picking the right filesystem across Win, Mac, and Linux

Tuxera, a company that provides both open source and commercial filesystem drivers, announced the millionth download of NTFS for Mac today — that’s a large number, with many or most downloads being the free NTFS-3G solution.

We use NTFS-3G on Mac OS 10.4 here, in combination with the Plugable USB 2.0 SATA All-in-one Storage Dock and large TB+ SATA drives. Along with built-in NTFS support on Windows XP and up, and all recent Linux distros, this lets us easily swap a single USB cable between Windows, Mac, and Linux and have all three be able to read and write the drive(s).

Overall, this is a good solution for developers who have to span multiple platforms, for people who use boot camp to switch between Mac and Windows, or for increasingly common multi-platform offices that are using external storage docks for backup.

And it’s nice having a both an open source and a (better performing) commercially supported option.

It used to be that the venerable FAT32 filesystem was best way to format a drive to make sure you could easily read and write it from Windows, Mac, and Linux. But FAT32 has some limits that are especially problematic for today’s large drives 1 TB and up:

  • Hard limit of 4GB on any individual file (think home movies of 30 mins or more)
  • FAT32 needs large cluster size for large disks – which means wasted disk space in the case of many small files
  • Partition size limits that can get as small as 32GB, and certainly hit at 2TB

There are various ways to read and write filesystems native to one OS on another. But there are also lots of pitfalls. All things considered, NTFS is the best compromise today.

For more background: