Going BlueTooth

[rigidigital]

I have been doing a litle thinking. My app needs to send data from a keypad. I have mucked about with UHF chips. I think blutooth had advantage of queing transmissions so I can be sure no matter how many people are sending me data to the pc from keypads I will recieve all transmissions much like you get all your text messages on mobile phones even when seversal people send you a text at the same time.

So Ill need some type of bluthooth reciever and bluetooth transmitters on each keypad.

What do you think of that ??

Mike.

 

[rigidigital]

Just activating reply notification.

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[Jeremy Leach]

Not being funny, but all you tell us about your project is 'My app needs to send data from a keypad', so I can't really see how we have much to think about

Keypad, kepads? What data? Why? Who else is sending data to your PC?

 

[hippy]

Bluetooth dongles for PC's are relatively low in price these days but Bluetooth to serial receivers and transmitters are still very expensive. You will also need to be able to interface with the dongle and read the data on the PC.

 

[alband]

http://www.csr.com/home.php
http://www.csr.com/products/bcrange.htm

These are serious little (and I mean little) chips that Motorola at least used to use in their bluetooth headsets (I don't know if they still use them).

As said though, more details are needed.

 

[manuka]

I'm a great fan of 2.4GHz wireless data, but have surely mentioned a zillion times that basic BT's/ZigBee's very low power & microwave freqs. mean ranges will be only 10s of metres- at best! Almost anything in the LOS path will block signals.

Both these technologies offer high data rates of course, but surely 10s-100s kbps will not be needed for keypad/board work? Just what is your application?

That being said, the more powerful Class 1 BT is certainly capable of longer ranges (I've easily managed ~½ km with simple parabolic reflectors), & all manner of smart BT applications & dongles abound. However prices are at the US$$ level,with often cussed interfacing, & hence (for PICAXE work) IMHO you'd be better off using Digi's well established "XBee" ZigBee offerings.

Lower freq. & cheap 433 MHz UHF units may best suit such slow keypad work, & if data collisions arise then set up some 2 way "busy/resend" system.