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Complicated Stopwatch

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FatNFurry

Programmer
Feb 17, 2004
3
US
First of all, just FYI: I'm a total newbie to VHDL, so treat me as such. I have never done any of the things I am describing in the following thread.

Allow me to explain my situation:

I do timing and results for foot races in Wisconsin. Basically, I start a timer when the race starts. As the runners finish, I take down the time it took them to run their race and their "bib number" (a number they wear on their chest to identify themselves). When the race is all done, I print out everyone's times.

I'm trying to create a stopwatch that attaches onto a runner's wrist and has the capability to start timing when it receives a radio signal.

When the runner crosses the finish line, I want the stopwatch to stop and send the time and bib number that it recorded to a SQL database, or a text file or something somewhere on the computer so I can manipulate it and print it out. What I was thinking of doing is using a USB device that is connected to the computer the whole time. It receives the radio signals that the stopwatch transmits.

These stopwatches also have to be cheap, as there are sometimes 500 runners in a race. I have ExpressPCB which allows me to order custom-built boards in large quantities for a discount.

Can someone give me a push in the right direction?


Thanks!
Rick
 
There are systems that do this already. I believe they work using RFID tags that you attach to the runners shoe (probably tie it into the lace?). Then there is a mat at the finish line that when trod on will log the runner.

Of course the timing will not figure out who is the winner in a photo finish, but I imagine it would be accurate to 1 second, and probably better than you could do with a stopwatch.

If you do want to do it yourself. I don't think VHDL is the right group. But im not sure that a group exists for hardware development, so this is probably as close as you can get.

I imagine there are devices out there for detecting the RFID's that are fairly cheap and just connect up to a
CPU. So no need for an fpga/pld and therefore VHDL (unless its needed to connect to the CPU).

In fact you can probably buy off the shelf RFID readers and just write the software yourself.

--
 
I would buy the stuff that's already out there, but I'm trying to keep it low-cost. That's the whole point of doing it myself, other than the experience I will develop. So you think I can just get some components from Radio Shack and put something together without VHDL?



Rick
 
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