xiQ - Frequently Asked Questions¶
- xiQ - Frequently Asked Questions
- What is USB 3.0 SuperSpeed?
- Do xiQ cameras support USB3 Vision Standard?
- How will my machine vision application benefit from using USB 3.0 camera?
- What is the real transfer speed?
- What operating systems and software is supported?
- Are XIMEA xiQ cameras Backward compatible to USB 2.0?
- What are the maximum cable lengths?
- How to synchronize multiple cameras?
- What voltage should be applied to Digital Input of xiQ to turn it on/off?
- What is implementation of Digital Output (VDO) of xiQ?
- How to optimize software performance on high frame rates?
- Does USB3 have a positive effect on EMC (Electromagnetic Compatibility)?
- What type of transfer do XIMEA USB3 cameras use for image streaming?
What is USB 3.0 SuperSpeed?¶
USB 3.0 is the latest major revision of Universal Serial Bus (USB) standard which brings transfer speed of 5Gb/s and enables delivery of up to 5W of power to the target device.
It uses communication technology similar to that of PCI Express Gen2 .
Yes. XIMEA is a member of USB3 Vision Technical Committee and xiQ cameras support the standard being designed to be compliant with USB3 Vision from the moment of its release.
xiQ camera's firmware can be updated in the field, and even cameras delivered before release of the standard have the possibility to update its firmware to fully comply with benefits of USB3 Vision standard.
Speaking of benefits, USB3 Vision has the following advantages over simple USB 3.0 devices: higher bandwidth, more power, CPU efficiency and mainly reliability.
First models have already been tested successfully by the Committee and its members during plugfests and therefor comply with USB3 Vision Standard.
List of models : MQ003MG-CM, MQ003CG-CM, MQ013MG-E2, MQ013CG-E2, MQ013RG-E2, MQ013CG-ON, MQ013MG-ON, MQ020CG-E2, MQ020MG-E2, MQ022CG-CM, MQ022MG-CM, MQ022RG-CM, MQ042CG-CM, MQ042MG-CM, MQ042RG-CM
How will my machine vision application benefit from using USB 3.0 camera?¶USB3 provides many different advantages like:
- Increased performance with bandwidth much higher than USB 2.0, Firewire and GigE interfaces
- Remarkable miniaturization of size and footprint
- Lower power consumption and heat dissipation through better design and management
- No frame grabbers needed
- Newest sensors and components as well as accessories and software
- Multiple cameras support
- Acceptance and standardization
- Reliability and low CPU usage
- Plug and play simplified integration
- Resulting in overall reduced system cost.
What is the real transfer speed?¶
xiQ cameras being the fastest among USB 3.0 can deliver up to 400 MB/sec.
Maximum transfer speeds and other aspects to compare:
|Interface||Transfer speed||Cable length||Multiple cameras||CPU Usage||System cost|
|IEEE1394A||45 MB/s||10 m||Place 1||Low||Medium|
|CameraLink base||255 MB/s||10 m||Place 2||Medium||Highest|
|GigE||100 MB/s||100 m||Place 3||Medium||Medium|
|USB 2.0||49 MB/s||5 m||Place 2||High||Lowest|
|USB 3.0||400 MB/s||100 m||Place 1||Low||Lowest|
(Please note: some of the information in the table is subjective)
Maximum speed and reliability requires that certain conditions are being met:
Please verify that you are using compatible hardware and software. To achieve maximum bandwidth of the camera follow the High Performance Hardware notes.
xiCOP - XIMEA Control Panel is a free software tool that facilitates with the task of verification of XIMEA USB3 Vision camera installations, helping to find bottlenecks and achieve the best results.
What operating systems and software is supported?¶
XIMEA puts a lot of emphasis on the support and interoperability with different software and hardware vendors, which is why our USB3 cameras support not only the usual Windows, but also popular Linux and specific Mac OSX. Recently added due to customer requests - ARM.
From our wide range of supported Libraries these 4 currently comply with the USB3 Vision Standard: National Instruments with LabView, MVTec with Halcon, Matrox with MIL and A&B Software with ActiveUSB .
Are XIMEA xiQ cameras Backward compatible to USB 2.0?¶
Yes. If consumers prefer, they can still utilize their USB 2.0 peripherals with slower speed of data and power transfer.
Regarding the power - USB 3.0 provides more efficient power management and allows effective 4.5W which is higher than USB 2.0 with it's 2.5W.
The USB Battery Charging 1.2 specification allows up to 7.5 W.
USB 3.0 also has an improved way of entering and exiting low-power states which removes power consuming polling.
Another difference of USB 3.0 are screw-locking connectors.
What are the maximum cable lengths?¶
There is a popular myth going around which originates from the early days of USB 3.0 and is kept alive by vendors of devices with other interfaces.
It states that maximum cable length for USB3 is 3m or 5m at most.
This is for a while now not true anymore.
XIMEA offers lengths ranging to 8m, but also has successfully tested active repeaters capable of lengths from 10m up to 55m and fiber extenders which are effective to 100m distances.
How to synchronize multiple cameras?¶
First some overview: theoretically, maximum number of devices on a network can be up to 255 units.
Of course as with the speed and other parameters, in practice the number depends on the setup and specifically on the host controller.
Host controllers presently available can support around 30 devices (where hubs are considered a device).
To successfully synchronize, you can use the camera's GPIO trigger.
XIMEA cameras support both hardware and software triggering.
How to handle multiple cameras can be found HERE and description of the synchronization process can be followed HERE
Note: maximum rate at which you can trigger the camera may be lower than the maximum overall frame rate of the camera model.
What voltage should be applied to Digital Input of xiQ to turn it on/off?¶
Following table shows different levels of Voltage on Digital Input (VDI) on xiQ and their logical interpretation.
|Logical level||VDI 24V GPI||VDI 5V-24V GPI|
|Off (zero)||0-5Vdc||0-2 Vdc|
|On (one)||15-24Vdc||4-24 Vdc|
Maximal input voltage 24Vdc.
All inputs and outputs are opto-isolated
What is implementation of Digital Output (VDO) of xiQ?¶
VDO is opto-isolated NPN open collector type, max. load current 25mA, max. open voltage 24Vdc.
How to optimize software performance on high frame rates?¶
In order to get all captured frames in extreme conditions - buffering setup in application should be optimized.
To implement it please read our How to optimize software performance on high frame rates article.
Does USB3 have a positive effect on EMC (Electromagnetic Compatibility)?¶
Interestingly - yes.
USB 3.0 devices have so called SSC (spread spectrum clocking) that adjusts the signal spreading the energy over a wider frequency band.
SSC is effective in lowering electromagnetic emissions.
What type of transfer do XIMEA USB3 cameras use for image streaming?¶
xiQ line of cameras use bulk because it guarantees delivery, instead of isochronous that guarantees bandwidth.