Troubleshooting and performance
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Alvium USB Cameras User Guide V1.1.0
Dividing bandwidth between devices on a
common USB 3.0 / 3.1 Gen 1 bus
Ideal setup for two cameras
Preconditions
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Control traffic is ignored.
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The possibility of the host being busy with other tasks is ignored.
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Cameras share 100% bus bandwidth.
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Cameras need 100% bus bandwidth in total.
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Cameras stream in the same way because they are the same model and have
identical settings.
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No other device is connected.
Result
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Bandwidth is divided by two, cameras get assigned 50% bandwidth each.
For three cameras, the bandwidth is 33.3% each.
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If one camera sends no data, the other camera will be assigned 100%
bandwidth. To always assign 50% to both cameras, they have to be controlled
to use no more than 50% bandwidth each.
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If the PC cannot process the images received from a camera, images are
corrupted.
Best practice for bandwidth management
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To assign maximum bandwidth to a camera, make sure your camera is the only
device on the bus.
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Avoid that devices, such as a monitor or a mouse, share bandwidth with the
USB3 Vision camera connected to the same bus.
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For maximum bandwidth, use a current version host controller card.
See
https://www.alliedvision.com/en/support/technical-documentation/
.
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USB3 Vision devices use bulk transfer. Avoid using other transfer modes.
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Control bandwidth by assigning the desired amount to the separate cameras.
