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GeneralRe: ROUTE command Pin
Super Lloyd25-Aug-15 16:33
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AnswerMessage Closed Pin
29-Feb-16 22:29
MemberEdward Santiago29-Feb-16 22:29 
AnswerMessage Closed Pin
29-Feb-16 22:31
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QuestionRecommendations/experiences please Pin
Matt T Heffron31-Jul-15 11:37
professionalMatt T Heffron31-Jul-15 11:37 
AnswerRe: Recommendations/experiences please Pin
Munchies_Matt11-Aug-15 1:49
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AnswerRe: Recommendations/experiences please Pin
Matt T Heffron11-Aug-15 6:26
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GeneralRe: Recommendations/experiences please Pin
Munchies_Matt11-Aug-15 6:35
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GeneralRe: Recommendations/experiences please Pin
Matt T Heffron11-Aug-15 11:15
professionalMatt T Heffron11-Aug-15 11:15 
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 Frown | :(
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

GeneralRe: Recommendations/experiences please Pin
Munchies_Matt12-Aug-15 0:20
MemberMunchies_Matt12-Aug-15 0:20 
GeneralRe: Recommendations/experiences please Pin
Matt T Heffron12-Aug-15 7:43
professionalMatt T Heffron12-Aug-15 7:43 
GeneralRe: Recommendations/experiences please Pin
Munchies_Matt12-Aug-15 8:22
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QuestionNotebook Specs Pin
C-P-User-321-Jul-15 19:08
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AnswerRe: Notebook Specs Pin
Richard MacCutchan21-Jul-15 20:28
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GeneralRe: Notebook Specs Pin
C-P-User-329-Jul-15 13:47
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GeneralRe: Notebook Specs Pin
Brisingr Aerowing29-Jul-15 15:05
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GeneralRe: Notebook Specs Pin
C-P-User-329-Jul-15 15:29
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GeneralRe: Notebook Specs Pin
Albert Holguin25-Aug-15 14:55
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GeneralRe: Notebook Specs Pin
C-P-User-329-Jul-15 15:32
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GeneralRe: Notebook Specs Pin
Brisingr Aerowing29-Jul-15 18:45
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GeneralRe: Notebook Specs Pin
Albert Holguin25-Aug-15 15:02
professionalAlbert Holguin25-Aug-15 15:02 
GeneralRe: Notebook Specs Pin
C-P-User-326-Aug-15 3:37
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GeneralRe: Notebook Specs Pin
Albert Holguin26-Aug-15 3:59
professionalAlbert Holguin26-Aug-15 3:59 
GeneralRe: Notebook Specs Pin
Albert Holguin25-Aug-15 14:53
professionalAlbert Holguin25-Aug-15 14:53 
GeneralRe: Notebook Specs Pin
Richard MacCutchan29-Jul-15 21:05
mveRichard MacCutchan29-Jul-15 21:05 
GeneralRe: Notebook Specs Pin
Afzaal Ahmad Zeeshan29-Jul-15 22:53
mveAfzaal Ahmad Zeeshan29-Jul-15 22:53 

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