Arie Verveer wrote:

> Hi, In mid august, Doug ( Doug  ) mentioned a
> project that was working on using a simm-sized micro controller that
> implements TCP/IP  for a strong motion devices. Since then I have
> purchased two of these controller boards and the company that
> provides them are about to release an upgrade to the software the makes
> it easier to access I/O through the units programming language, Java.
> They have already released the documentation.  Given easy access to the
> high speed hardware it would be simple to add some A/D chip. At the
> moment the device's supported I/O is a "one wire interface" and serial
> port.  I'm looking forward to the upgrade and access to the "real" I/O.
>
> My vote is for Doug's concept for the strong motion device for the schools.
> Though the controller boards should have the better I/O software.
> Better I/O means a huge range of possibilities.
>
> The device could then be plugged into a local school network. All you need
> to do is give it a "IP" address. This coupled with a good 12 bit multi-channel
> A/D chip and support software would make an impressive interface.
> A/D chip -> LTC1290 ?
>
> The boards are cheap and powerful: see   http://www.ibutton.com/TINI/
> Arie

I second the idea of using the TINI board for the processor and network interface.

For the sensors it seems like the silicon sensors used in the USGS design would
meet most requrements. I would however eliminate the hand tweaked low pass filters
of the USGS design  by using  Delta-Sigma A/D Converters such as the Burr Brown
ADS1210 Without a lot of effort you can get 20 bits out of these converters and
they are inexpensive.


--
Jim Hannon
http://soli.inav.net~jmhannon/
42,11.90N,91,39.26W
WB0TXL



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