I don't see why you don't do this with bluetooth. If you have a
headset that you will always have in your bag or on your person (ie. it
doesn't get left behind with your phone if you leave) you can run this
script on your Neo. You just have it constantly pinging the headset
and testing the rssi of the connection. When it goes below a point,
have it play a siren ring tone.
<br><br><a href="http://www.goitexpert.com/entry.cfm?entry=Use-Your-Bluetooth-Cell-Phone-as-a-Proximity-Card-for-your-Laptop" target="_blank" onclick="return top.js.OpenExtLink(window,event,this)">http://www.goitexpert.com/entry.cfm?entry=Use-Your-Bluetooth-Cell-Phone-as-a-Proximity-Card-for-your-Laptop
</a><br><br>It seems to work for me. For my phone/dongle combination,
I would probably set the distance at a 0 or a -5 for the minimum RSSI
before making a siren noise.<br><br>For the script in the link, you would not have anything for NEAR_CMD and FAR_CMD="mpg123
siren.mp3" for example.<br><br>Does
this sound feasible? It could give you an excuse to get a bluetooth
headset :-). Of course ,then again, if your headset runs out of
batteries then your phone will start alerting everybody on the train
while you struggle to kill the looping background process :-).
<br><br>Randall<br><br><div><span class="gmail_quote">On 11/8/07, <b class="gmail_sendername">Henryk Plötz</b> <<a href="mailto:henryk@openmoko.org">henryk@openmoko.org</a>> wrote:</span><blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">
Moin,<br><br>Am Fri, 9 Nov 2007 10:22:24 +1300 schrieb Robin Paulson:<br><br>> ideas? any other absent-minded daydreamers out there? is RFID the way<br>> to go? are there any unlicensed parts of the radio spectrum that are
<br>> free for use by anyone using low-powered radio transmitters?<br><br>It should be possible to get <a href="http://www.openbeacon.org/">http://www.openbeacon.org/</a> to do just<br>that. The tags can talk to each other or to a base station. You
<br>should be able to program two tags to ping each other in regular<br>intervals and then make themselves noticeable when they lose contact.<br>(There are two I/O pins that could be connected to an external piezo<br>buzzer or vibrator.)
<br><br>In principle it should even be possible to fit one of the tags into the<br>Neo, though that might require a new tag PCB design. I think roh already<br>had dreamed about something like that some time before (in a different
<br>context).<br><br>The radio transceiver used by OpenBeacon operates in the 2.4GHz band,<br>but does not follow any particular standard (e.g. no Bluetooth, no<br>Wifi). But it's small and very low power.<br><br>--<br>
Henryk Plötz<br>Grüße aus Berlin<br>~ Help Microsoft fight software piracy: Give Linux to a friend today! ~<br><br>_______________________________________________<br>OpenMoko community mailing list<br><a href="mailto:community@lists.openmoko.org">
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