USB Test |
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Tests the USB (Universal Serial Bus) communications ports connected to the PC. The number of USB devices to test can be set in the USB test preferences window. A USB port loop back plug is required to run this test. The USB2 loopback plug provides a wider range of test for USB 1.x and 2.0 (USB 2.0 supports rates up to 480Mb/sec). These can be purchased from the PassMark web site (www.passmark.com).
Using a USB2 loopback plug and BurnInTest, it is possible to,
Using these plugs on a system that is functioning correctly, you can expect error free loopback transfer speeds of around: 5 – 7 Mbits/sec per port. To reach this level you need to have the USB test duty cycle set to 100%. Up to 10 of these USB test plugs can be simultaneously connected to a PC (providing that free USB ports are available on the PC or on a down stream hub). Note: If required, both USB1 and USB2 loopback plugs can be used to test different USB ports simultaneously.
Each test cycle corresponds to 8000 data blocks (4000KB).
The number of Operations (‘ops’) corresponds to the number of bytes sent and received. The duty cycle affects the time spent waiting between cycles. Each plug also has its own serial number stored in EPROM, on the plug, so it is possible to identify each plug when multiple plugs are connected. USB2 loopback plugs are firmware controlled and upgradeable. The USB test sends data to the USB loopback plug in 0.5KB blocks. The USB loopback plug receives this data, copies it to a new buffer and transmits it back to the PC. The PC compares the data in the block for an exact match, and then builds a new packet of random data bytes before sending it back to the PC. Any differences between the data send and received is flagged as an error.
USB test window
The following information is displayed in the USB test window.
USB Identity The device number, unique device serial number and the bus and port number the plug is connected to are displayed. The device number is determined by the order in which plugs are connected and disconnected and is not linked to a physical USB socket on the PC. (Note that this is different from Serial and Parallel ports). The device serial number is collected during the USB device enumeration process and comes from the memory (EEPROM) in the plug itself.
Bytes Sent The number of Kilobytes sent to the USB device.
Bytes Rec The number of Kilobytes received from the USB device.
Throughput The number of Megabits of data received and transmitted in the last second.
Ave. Throughput The average number of Megabits of data received and transmitted per second since the start of the test.
Errors The number of errors that have occurred (i.e. Transmitted data does not match received data). |