[ltp] Re: OT: usb data capture hardware?

[Uwe Bonnes]

Richard Neill <rn214@hermes.cam.ac.uk> wrote:
> Dear All,

> Please excuse this being slightly off-topic: I thought someone here may 
> have experience of what I'm trying to do.

> Basically, I have an astrophysics sensor system which generates a 16-bit 
> wide output (from an ADC), with a rising-edge clock every time the 
> output has changed.  The data rate is somewhere between 1-5 MHz, and I 
> need to get this into a computer.

> So far:

>    1)  It's too fast for a parallel port (unfortunately - or it
>        would be ideal)

>    2)  The FTDI chip system, such as the DLP-245M is nearly ideal:
>        it implements a parallel port over USB, and has pre-existing
>        GPL drivers - but it is only USB 1.1, so too slow.

>    3)  The current solution I've been fighting with is a QuickUSB Module,
>        for which we have reverse-engineered drivers, but it's pretty
>        ghastly, and not reliable.


> So, any Ideas?


Look at usrp (universal software defined radio). Just featured in slashdot
or
http://comsec.com/wiki?UniversalSoftwareRadioPeripheral
It used USB hardware ( Cypress FX2 and Altera Cyclone) to stream data in
and/or out the PC at more than 20 MByte/s .

The SSRP http://oscar.dcarr.org/ssrp/ is a stripped down project, probably
more adequate to your problem.

But no more parallel port involved.

Otherwise use the EPP or ECP mode of the parallel
port. http://www.fapo.com/1284adv.htm talks about 2-5 MB/s possible. 

-- 
Uwe Bonnes                bon@elektron.ikp.physik.tu-darmstadt.de

Institut fuer Kernphysik  Schlossgartenstrasse 9  64289 Darmstadt
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