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Packet-Master USB480

Packet-Master USB480

High Speed, Full Speed and Low Speed
USB Bus Analyser

  • Analyse any speed of device or host
  • On-the-Go analysis
  • 32 Mbyte FIFO
  • Hardware triggering
  • Highly cost-effective development solution



The Packet-Master USB480 is a Hardware USB Bus Analyser, intended for development of Low, Full and High Speed USB devices and hubs etc. It comes complete with our Windows application Graphic USB for capturing and displaying every detail of the data interactions on a USB link.

(For new enhanced model with Advanced Trigger functionality see Packet-Master USB480+)

(For Full/Low Speed Only Analyser see Packet-Master USB12)

Download Packet-Master Product Data Sheet (PDF)

Download Packet-Master USB12 / USB480 / USB480+ Manual (1.25 Mbytes)

Download the Latest version of the GraphicUSB Application

What's in the new version?

Buy Now

See This Month's Special Offer on Packet-Master USB480

USB Made Simple


Total Solution For USB Analysis

For those developers requiring an analysis solution for High, Full and Low Speed USB, we have developed the Packet-Master USB480™.

In addition to the features of the USB12, we have added High Speed capability, On-The-Go analysis, and a hardware trigger port.



Hardware Features

Front View
  • Power Indicator
  • Activity indicator shows presence of data exchanges
  • Trigger indicator shows when BNC trigger is enabled
  • Integral Capture Start and Stop buttons and Capture Indicator
  • USB through-connectors for device under test
  • Analyses Low Speed (1.5 Mbit/s), Full Speed (12 Mbit/s), High Speed (480 Mbits/s) or a mixture of these speeds
  • Automatically detects speed of link under test
  • Economically priced
  • Fully Lead Free and RoHS compliant
  • Incorporates 32 Mbyte FIFO to prevent loss of data
  • Bus-powered for convenience of use
  • Input for optional external power (not required, but useful if host won't configure a high-power device)
  • High Speed USB (480 Mbit/s) connection to host PC
  • BNC Trigger socket input or output under software control
  • Feature connector provides signals for oscilloscope or logic analyser
Rear View



Software Overview

The Packet-Master USB480 owes a large part of its functionality to the GraphicUSB application, which is supplied with the unit. A simple, yet information-rich display allows you to view every detail of a capture.

This shows the organisation of the screen after a typical capture:


Software Features

  • Capture controlled from USB480 unit buttons or BNC trigger input, or from GraphicUSB Application.
  • Captured document shows every detail of data transactions graphically for a fuller understanding of the USB protocol. This includes a detailed visual analysis of each packet.
  • Transactions are grouped and summarised with a header row in the event pane. Control transfers are summarised with a special header row.
  • Filters allow less significant information to be removed from the display to allow you to concentrate on the critical data.
  • Each event is analysed in detail, with any significant features explained, and possible errors or warnings highlighted.
  • Data pane shows the data content of any packet.
  • Comprehensive search functions.
  • Events display, detail analysis or data can be printed.
  • Standard software up-grades are free of charge from our web site.
  • Software can be freely used as a viewer in the absence of the Analyser Hardware.
  • A multi-document interface allows comparison between captures.
  • Capture size only limited by RAM size.
  • Optional Class Analysis Modules.

Download GraphicUSB and try it out

The downloadable package contains the full current release of GraphicUSB, together with some sample captures for you to examine. The sample files are in a folder:

C:\Program Files\MQP Electronics\GraphicUSB\Samples

This also demonstrates how you can view capture files in the absence of a Packet-Master USB480 Analyser.


Mixed Speed on a Single Link

This view of part of a screen shot from Graphic USB shows a representation of data being transferred at two different speeds on the same link. Each packet is preceded by a coloured marker indicating High Speed, Full Speed or Low Speed. This makes the function of the PREAMBLE packet very clear, and shows precisely how split transactions work. Each event has a precise timestamp (left). Notice also the detailed timing information for Hub Setup time, End of Packet duration, and IDLE state time.

View by Control Transfers
(less significant events filtered)

By clicking on the filter buttons for less significant event types, the sequence of top-level control transfer headers may be viewed in isolation. This ability to view information at an appropriate level of complexity makes Graphic USB an invaluable tool for getting straight to the heart of the matter. In this example we have chosen to display top-level transfer information plus bus state events.

Full Analysis and Data Panes

By clicking on an event row in the event pane, a complete analysis of the event is displayed in the analysis pane, and the data content is shown in its entirety in the data pane. Where relevant, any information selected in the analysis pane is highlighted in the data pane for easy identification. All standard requests and descriptors are analysed in detail. Discrepencies are described.

Optional Class Analysis Modules

A number of Class Analysis Options are in preparation. The following are now available:

  • Human Interface Devices (HID)
  • Hub Class
  • Communications Class
  • Printer Class
  • Mass Storage Class
  • Audio Class
  • Video Class (V1.0, V1.1)
  • Vendor Class

Registering an option allows Graphic USB to display Class transfers in a more readable form.


The screen shot to the left shows the analysis of a HID Report Descriptor.

The shot below shows the results of the built-in 'HID Report Descriptor' parser. Each report defined by the Report Descriptor is identified and displayed.


With the HID Class Analysis enabled, each HID report is identified, and the contents analysed.

Examining the analysis of existing devices is an excellent way to learn how a class works, and it has never been easier to reveal the building blocks, than with Graphic USB.

Test Set-up Connections

To achieve a good capture rate it is important to provide a suitable test environment. The Packet-Master USB480 should preferably be hosted by a good performance PC which must have a high speed USB connection. This USB host controller should not be shared by any other USB device while doing the testing.

It is theoretically possible to use the same host computer for the Packet-Master USB12 and for the Host Under Test. We do not recommended this, but if it is absolutely unavoidable, then you must at least use a separate USB host controller for the device under test. If your computer does not have two host controllers then you will need to buy a plug-in USB host controller card.


As this test equipment, by its very nature, has to connect to a junction of two USB cables in order to probe the data on the link, it is important to keep the cables between the 'device under test' and the 'host under test' as short as possible (for example 1m), and to use good quality cables.



Quick and easy with self-installing software.

System Requirements
(for supporting Packet-Master USB480)

  • Pentium 3 - 600MHz
  • PC with High Speed USB port should be dedicated to the capturing. (Actual target device should be connected to a different Host Computer to ensure reliable capture bandwidth)
  • Windows XP (Service Pack 1 or better) preferred.
  • CD ROM / DVD Drive
  • 128MB RAM
  • 100MB space on Hard Disk

Note: A good performance machine is recommended for good capture rate.

Physical Specifications

Weight: 360 g
Dimensions: 190 x 140 x 32 mm
0°C - 40°C
Humidity: 20% - 80% non condensing


Electrical Requirements

The Packet-Master USB480 normally derives its power from the Host computer's USB connection.

Power: 225mA from USB host
Optionally zero mA from USB if powered externally



CE compliant.

Signals Available on Feature Connection

  • D+
  • D-
  • 60MHz Clock

Standard Accessories

Packet-Master USB480 comes complete with the following:

  • Graphic USB control software on CD
  • USB 2.0 cable x 2
  • Manual on CD

Optional Accessories

  • Feature Connector Terminating Board
  • External Power Supply

Software Options

  • Individual Class Analysis Options


  • Ex stock

This range of test equipment is manufactured in England to the highest standards by MQP Electronics. Our distributors should have no difficulty in supplying you quickly with any item. Specifications of our products can be found on our Web Site

If you require further information, our sales office will be pleased to advise. Our phone number is +44 1666 825 666.


Download Packet-Master Product Data Sheet (PDF)

Download Packet-Master USB12 Manual (PDF) (390 Kbytes)

Download the Latest version of the GraphicUSB Application

What's in the new version?

Buy Now

USB Made Simple