USB low speed and full speed qualifying devices

[wanderer]

The USB-IF Legacy tests are used to see if the USB 2.0 device under test plays nicely with low speed and full speed devices. To do that the test requires a low speed and a full speed qualifying device be connected during the test. I'm not sure what kind of device to use. I think a USB mouse is a lowspeed device. For a full-speed device I don't know what to look for. Any suggestions on where to find USB low speed and full speed devices?

Thanks

 

[mike]

The USB-IF Legacy tests are used to see if the USB 2.0 device under test plays nicely with low speed and full speed devices. To do that the test requires a low speed and a full speed qualifying device be connected during the test. I'm not sure what kind of device to use. I think a USB mouse is a low speed device. For a full-speed device I don't know what to look for. Any suggestions on where to find USB low speed and full speed devices?

Thanks

I'd call up technical support for a USB chip vendor and ask what they
use. Might take some struggling to get to someone who actually knows.
The first guy to answer the phone surely won't.

 

[Uwe Hercksen]

The USB-IF Legacy tests are used to see if the USB 2.0 device under test plays nicely with low speed and full speed devices. To do that the test requires a low speed and a full speed qualifying device be connected during the test. I'm not sure what kind of device to use. I think a USB mouse is a low speed device. For a full-speed device I don't know what to look for. Any suggestions on where to find USB low speed and full speed devices?

Hello,

USB memory sticks might be full speed devices, but not all of them. If
speed is not specified, it may be somewhat lower. USB diks is another hint.

Bye

 

[Jasen Betts]

Hello,

USB memory sticks might be full speed devices, but not all of them. If
speed is not specified, it may be somewhat lower. USB diks is another hint.

Most are "high speed" "full speed" is the lower USB 1 maximum speed,
Yeah it's confusing, I was half way through a reply before I remembered.



[1007869.484147] usb 6-2: new full-speed USB device number 4 using uhci_hcd
[1007869.644190] usb 6-2: New USB device found, idVendor=067b, idProduct=2303
[1007869.644200] usb 6-2: New USB device strings: Mfr=1, Product=2, SerialNumber=0
[1007869.644207] usb 6-2: Product: USB-Serial Controller D
[1007869.644213] usb 6-2: Manufacturer: Prolific Technology Inc.

It's a common usb-to-rs232 cable. This one bears "Unitek" markings.
http://www.unitek-products.com/en/product_detail.php?id=12

The chip is Prolific "pl2303" and readily available if you want to build your
own or can't find one locally.