Electronic – Bluetooth SPP (Serial Port Protocol) and Cobra Tag

androidbluetoothprotocolserial

I have been trying to build something similar to the Cobra Tag (Check out the video). I have written a prototype android app which uses SPP to connect to a bluetooth module and exchange commands, which is working great. But, i have a few queries

  • From what appears, does Cobra Tag also use SPP or any proprietary custom profile ?
  • I am able to connect to a single device over SPP and do the data exchange, how do i go about connecting to multiple devices simultaneously. Does Bluetooth/SPP support that ?
  • Should i be using any other bluetooth profile/protocol which would be more efficient for this purpose ?

Best Answer

Check the Cobra Tags FAQ

Answer to first and second question.

Can I use a Cobra or other manufacturer’s Bluetooth headset for handsfree talking while using this product?

Yes you can. The Cobra Tag uses a different Bluetooth communication link than the headsets (called serial port profile) so they can both work together.


How many Cobra Tags can be connected to one mobile phone?

The maximum number with some phones is 7. The maximum number that can be paired with iOS devices is 1. This is based on a technology limitation. It seems that some phones can’t simultaneously handle 7 Tags and are better off with 1-5 maximum.


Answer to Third question.

SPP emulates a serial cable to provide a simple substitute for existing RS-232. Architecture of cobra tag shows it doesn't need complex data manipulation and just requires a few set of commands for its operation. I'll suggest sticking to this profile only.