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The device vendor provides both a driver and an API dll (both 32 bit) to talk to the device.
The device uses USB bulk endpoints.
The data is guaranteed to be available to the host, however, if the host gets behind, then the device will skip performing the next data acquisition 
The amount of data is actually pretty small, it is the latency that is the bigger issue.
Each device acquisition is a little less than 40kB, at 15Hz rate: ~610kB/sec data rate.
However, the effective acquisition rate is twice that since the device will not start an acquisition until all of the previous acquisition data has been read. The device takes approximately 30ms to readout an acquisition. And 30ms is about the shortest acceptable data acquisition "exposure time".
The experiment I ran was using c# software I wrote to retrieve data from the device using an API function which spins up a separate thread to pull the data into a managed buffer. The application has a separate thread which pulls the data from the buffer and "drops it on the floor". (This is a best case: minimal application computation, though not realistic. Actual application includes significant computation.)
The device has a status line indicating if it is ready for an external trigger to begin an acquisition. We have an STmicro eval board running simple SW to provide triggering at a specified interval and a counter of occurrences of status not ready when a trigger was scheduled.
I specified an exposure time of 1ms since the exposure time is not concurrent with the data transfer.
On an i5 Quad core Windows 7 PC, triggering at 40ms is required to ensure no "not ready" conditions were detected. If I added writing the acquired data to a local file, then there were many "not ready" detections. The actual application has significant additional computation required.
"Fairy tales do not tell children the dragons exist. Children already know that dragons exist. Fairy tales tell children the dragons can be killed."
- G.K. Chesterton
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SO on WIndows you cant get enough reads down to their dll/driver to get data off the device quick enough, but on winCE you can?
I would approach them and ask why this is. SOunds like their API-dll/driver isn't working properly. If they sell windows SW to go with the device, it HAS to be able to work properly.
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The recommendation to use Windows CE came from the device vendor.
The "real time capabilities" of Windows CE, and the ability to strip it of anything else that could interfere with servicing the USB device are the basis of their recommendation.
The Windows CE system would mediate all communications with the device (only data collection operates in a time sensitive mode).
Communication with the host necessarily would be at a lower priority than servicing the USB.
"Fairy tales do not tell children the dragons exist. Children already know that dragons exist. Fairy tales tell children the dragons can be killed."
- G.K. Chesterton
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What? They must be incapable of writing a usable windows driver then and their suggestion is a kludge.
I repeat, kernel code is perfectly capable of pulling data off a USB device. It can handle data way way quicker than a USB device can produce it. All they need to do id provide a half decent driver and you wont have to buy extra hardware.
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Can someone point me to a useful understandable tutorial on how to read the specs on notebook computers ?
I do not understand why desktop computers have specs written in a way that is clear and obvious, while notebook computers do not.
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C-P-User-3 wrote: how to read the specs on notebook computers
What exactly do you mean by "how"? Look at the detail in their published documentation.
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Okay, these guys have this computer advertised: Lenovo ThinkPad Edge E550 20DF
These first six specs are clearly understood...
- 8 GB RAM
- 500 GB HDD
- DVD-Writer
- 15.6" 1920 x 1080 ( Full HD )
- 802.11ac
- graphite black
No Clue on these next two. Going to google. I think the Radeon is (or was once) a graphics card. I don't have any idea of how to put the first one into my brain, as a quantity, and then get that qualitative concept which flows out of the quantifiable item.
- Core i7 5500U / 2.4 GHz <---The "core" of my confusion
- AMD Radeon R7 M260
I think I know what these next two mean; and it makes me go "HUH ???"
- Windows 7 Pro 64-bit / Windows 8.1 Pro 64-bit downgrade
- pre-installed: Windows 7
I think this last one is a part number
This is the kind of stuff where I don't really understand what stores are telling me when they advertise a notebook computer. I'm sitting here asking myself what I'm getting for what I'm paying, and no clue on how to compare that against another machine with equally convoluted specs.
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Radeon is a graphics card from ATI (and a rather good one at that), and the CPU is an Intel i7 5500U (the number 5500U is a model number), running at 2.4 Gigahertz.
Did the specs really say a downgrade? If they did, they were right.
What do you get when you cross a joke with a rhetorical question?
The metaphorical solid rear-end expulsions have impacted the metaphorical motorized bladed rotating air movement mechanism.
Do questions with multiple question marks annoy you???
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Did the specs really say a downgrade?
Yes[^]
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They mean if you choose to use Windows 7 on it instead of 8.1 (or the newer 10). Depending on your needs, you may opt for one version or another. For example, in my regular business needs, I need a lot of software that I KNOW works on Win7, so if I need a business laptop, I'll choose that. On the other hand, if it's a personal computer, I'll probably choose the latest and greatest.
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Brisingr Aerowing wrote: the CPU is an Intel i7 5500U
Is there a place where I can get a visual matrix of which CPU has what parts inside ?
i.e., some way to compare apples to apples.
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Not sure. Google doesn't turn up anything.
I found a couple benchmarking sites:
CPUBoss[^]
And
CPUBenchmark.net[^]
But that's about it.
What do you get when you cross a joke with a rhetorical question?
The metaphorical solid rear-end expulsions have impacted the metaphorical motorized bladed rotating air movement mechanism.
Do questions with multiple question marks annoy you???
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C-P-User-3 wrote: Is there a place where I can get a visual matrix of which CPU has what parts inside ?
Err... CPU is the Central Processing Unit... i.e. there's nothing inside of it other than the microscopic transistors that make up the logical elements.
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Some have 2 cores, some have 4, and some have more.
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Yeah, that's something you can easily look up though. It's sort of trivial at this point that most CPUs have multiple cores and a shared memory cache.
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Brisingr Aerowing wrote: Did the specs really say a downgrade? If they did, they were right.
A lot of people still prefer Windows 7 over 8.1 or 10 (including yours truly). I'll upgrade on my own time, I have work to do.  
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Well none of that is specific to notebooks, most PCs of any configuration from tablets up will have some combination of similar items.
C-P-User-3 wrote: Core i7 5500U / 2.4 GHz
That is the Intel Core i7 processor running at 2.4GHz processor clock rate. The intel website will give you the full details and comparision with the slower i5 and i3 processors.
C-P-User-3 wrote: AMD Radeon R7 M260
One of the AMD graphics processors that provides the high resolution video.
The various Windows versions that you can (presumably) opt for.
All of which can easily be found by Google.
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Core i7 is just the product of Intel processors. If something isn't clear, Google is always there for you. Since the processor isn't clear, try this resource from Intel to learn more about that product of theirs. http://ark.intel.com/products/85214/Intel-Core-i7-5500U-Processor-4M-Cache-up-to-3_00-GHz[^]
Same thing for the Graphics card (yes, that AMD is a graphics card for your machine). What about this link to learn more about it? http://www.amd.com/en-us/products/graphics/notebook/r7-m200[^]
Windows version and the final notebook product item number are a few things that you would be using to find hardware or drivers related to your machine. Windows product is what you can change while purchasing the product. You can select from Windows 7 or Windows 8.1 Pro, your choice.
If you find difficulty in learning something or understanding, always try to Google for it. Google has a good base of search results for you. 
The sh*t I complain about
It's like there ain't a cloud in the sky and it's raining out - Eminem
~! Firewall !~
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Each and every machine that a manufacturer provides has a clear table list for their specifications. I have, as far as I searched, found it very easy to read the specifications for the machine.
The only thing that might make it hard for you to read and learn the specs is the UI and UX of the website. Can you point me to a notebook which doesn't have specs clearly written or explained?
The sh*t I complain about
It's like there ain't a cloud in the sky and it's raining out - Eminem
~! Firewall !~
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Afzaal Ahmad Zeeshan wrote: the UI and UX of the website
Uhm, yes, your comment is "spot on"
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I asked the internet search engines, and came across conflicting experts. (Who'da'thunkit ?)
If we build a card with a video camera which uses a Bluetooth connection back to "home base" so to speak, can we expect a robust and clear video result for the user ?
I'm not clear on how to do the arithmetic.
What times what, divided by what, gives me what result ?
Then of course, I need to consider things like theoretical scientific stuff on the internet -vs- what we're going to experience in real life; but that's a different conversation.
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In theory the data should be as good as any other transport mechanism, but only testing can tell you for sure. You do appreciate that Bluetooth is only for very short (<10 metre) distances?
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Richard MacCutchan wrote: ...Bluetooth is only for very short (<10 metre) distances...
Understood. The existing design ("dream" might be a better word after some recent feedback from my gang at work) will be boxes in the attic. It's all up in the air now.
Might not even happen at all.
Oh well, I thought it was a pretty good idea.
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Bluetooth doesn't penetrate walls (and ceilings) very well. I think you'll face a lot of signal quality problems.
The difficult we do right away...
...the impossible takes slightly longer.
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Something else to keep in mind are the data rates available in the Bluetooth standards. The rates are pretty low, so you could stream video but you'd have to do a bunch of compression and probably accept the fact that the video won't be all that good. Bluetooth works for audio because the data rates of compressed audio are very low.
See Bluetooth rates here (under "uses"): https://en.wikipedia.org/wiki/Bluetooth[^]
In contrast, WiFi rates are significantly better... so system design question to you might be, you can use Bluetooth, but why would you? What are the benefits from such a system?
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