In my experience at high sampling rates for multiple shimmers the PC was
never the bottleneck it was the  multiple Bluetooth radios not being able
to keep up with the packet send rate. I did have an oldish laptop at the
time although it was dual core. You have to make sure the app on the pc is
multithreading as efficiently as possible, which may be out of your control
with labview - mine was a C++ app.

Your mileage may vary.
Phil Reaston
CTO, iDi-dx
Phone:  (702) 291 8245
www.idi-dx.com

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On Tue, Jan 10, 2012 at 5:27 AM, mike healy <[email protected]> wrote:

> Hi Ram,
>
> A single Bluetooth master can only connect to a maximum of 7 slave devices
> at a time. However you could use multiple Bluetooth radios simultaneously
> on a PC (as masters) to scale as required. The problem here is that Windows
> does not support using multiple Bluetooth radios simultaneously. There are
> commercial products that can overcome this problem (and have successfully
> been used with Shimmers in the past), e.g.
> http://www.bluegiga.com/Bluetooth_Access_Servers.
>
> The sampling rate of the shimmers and the amount of data that is being
> read by the PC is also important, as the PC's processing speed can be the
> bottle-neck.
>
> Of course the channel bandwidth is also important, as there is only so
> much information that can be sent at one time.
>
>
> When using the 802.15.4 there is no practical limitations to the amount of
> shimmers that can be communicated with, again taking the bandwidth and PC
> processing speeds into account.
>
> Mike
>
>
> On Tue, Jan 10, 2012 at 10:41 AM, Ramanathan Subramanian <
> [email protected]> wrote:
>
>> Dear All
>>
>> Is there some pointer to the maximum number of Shimmer devices that one
>> can simultaneously connect to and record the data? It appears that using
>> the Shimmer Labview library, one can record data from 4 sensors
>> simultaneously, but is this the maximum limit?
>>
>> Thanks very much
>> Ram
>>
>> _______________________________________________
>> Shimmer-users mailing list
>> [email protected]
>> https://lists.eecs.harvard.edu/mailman/listinfo/shimmer-users
>>
>>
>
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