Re: Best Method to Download Data from a datalogger?

On 10 Oct 2006 15:02:01 -0700, "Mercy" <mercy.chang@xxxxxxxxx> wrote:

Hi All,

So my company has a datalogger for trucks and etc. It's a simple black
box design, nothing too fancy about it. Right now the clients download
data by bringing a laptop to the truck, plugging a null modem cable
into the RS232 of the black box and downloading the data as a text file
via HyperTerminal.

We want to make this process easier for our clients. I have the fun
task of exploring all the options from CF cards, USB flash drives (Thus
my previous post asking how to make a USB driver), blue tooth, RFID,
wi-fi and maybe even satellite.

I was thinking about using a USB flash drive, have it plug in... auto
download and tadda! All done. However, it seems that method is ...
more complex than I thought it'd be.

I was thinking about using the same approach except replacing the USB
flash drive with a CF card. However... before I dive into researching
how that would work... I'd like to get the opinions of you guys.

Which method would be easiest (aka, fastest and cheapest) to implement?

A minimum cost + development time option may be to keep the existing
application on the black boxes and replace the PC-side Hyperterminal
session with a simple app with a Big Red Button that takes care of the
serial session and handles some basic sanity checking of the data.

A slightly jazzier approach would be to do the above ('cuz NOBODY really
likes Hyperterminal) but replace the hardwired serial cable with a
couple of 802.15.4 dongles, one on each black box and one on the laptop.
Could be taken beyond a simple wired to wireless mod, like a small
amount of magic in the dongle cases to allow a unique address per truck.
The RF modules are relatively cheap, could be intermixed freely with the
existing hardwired serial method (so clients won't need to upgrade all
of their vehicles at once), and it could be written to be transparent to
the existing blackbox firmware (so no field upgrades required).

One option (I'm playing with the dev kit now) are the XBee modules from
<http://www.maxstream.net/products/xbee/xbee-oem-rf-module-zigbee.php>

--
Rich Webb Norfolk, VA
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