Comments: Using the BlueSMiRF


Comments 13 comments

  • I’m using two BlueSmirfs to connect my Photon Weather Shield to a serial LCD. Whenever power is lost to either unit, the connection drops and I have to restore it manually using my PC. Is there some way to programmatically do this from the code running on the Photon? So if the connection is lost, it will be restored automatically when power is restored?

    There seems to be a smiliar question above but it doesn’t look like it was really addressed.

  • I have a blueSmirf that (apparently) has a config timer that is always run out. When I plug it in the led blinks slowly, indicating timer has run out. Cycling power does not change the blink rate. Any way to fix this? I am using a Leonardo with RX and TX on D 10 and D11.

  • I am having trouble with connecting. I can us “I” to see what is around. Found my phone. Tried to connect to phone with C, <address> and the terminal reported “err” - not “trying” or “connection failed”. Is there some setting or something else I can check? And, yes, I am sure the address was correct including no <>.


  • Hi, I am having some problems entering in the setup mode: When I write the $$$ comand the red led starts blinking as I expect but I don´t recieve any feedback from the Serial Monitor. Can someone help me, please?

    • Just ran into this. If you are using a board aside from the Uno, software serial may not be available on pins 2 and 3. If your using a mega use 10 and 11. If not see the arduino website for usable software serial pins.

  • I somehow cant enter command mode again with my RN-42. It literally does nothing in my console when i type $$$ or whatsoever. Even from uploading the Sketch the RN doesn’t co CMD Mode. It worked when i first did it, but now i cant see it anymore neither get any infos from it or onto it.


    UPDATE I used another port now and it send me this:

    “CMD �No Remote Address!”

  • I have an application where this board will be inside a metal box, unavoidably. Would it be possible to remote the chip antenna, by un-soldering it and extending it with wires, say 6" or so through a hole in the box? Has anyone played around with remoting bluetooth antennae?

  • Suppose you’re wiring the BlueSMiRF (or, more precisely, an RN-42) directly to a serial pair, and there’s no computer on the serial pair–just a weather station, for example, or a camera with a serial port for PTZ. There’s no way to configure the RN-42 from the serial port side (and, obviously, until it connects, there’s no way to configure it from the BlueTooth side, either.) There are four GPIO inputs that set the RN-42’s power-up mode. Anyone get these to work in Auto-Master mode? So it automatically goes into pairing mode until its first connect, and after that automatically tries to connect to the saved MAC address of the other side? Just like, for example, your bluetooth phone earpiece?

  • To connect to the Rn-42 to an iOS check out this tutorial =>

  • Regarding BlueSmirf setup guide: If the user is connecting bluesmirf via the protoboard provided by sparkfun (DEV-07914) and attempts to use software serial as in this example, changing the TX and RX to digital pins 0 and 1 the bluetooth module interferes with serial communication and gibberish is obtained. The tutorial should specify that digital pins 0 and 1 are reserved for serial communication and if bluesmirf is connected to those pins software serial is not needed and the example code can be simplified

  • I’m having a difficult time getting this to work. It keeps saying the com5 port is already in use. why does it say this?

  • Hey guys,

    I don’t know if this is the right place to ask, but here it goes. When you have a RN42 module in slave mode connected to some other bluetooth module is any method to retrieve the MAC or BTname of the connected device.

    For example, I have a bluetooth device in slave mode another module gets in range and connects to my module (pairing was done before hand), how can I retrive its MAC.

    Thanks for your tutorials, you guys rock.

If you've found a bug or have other constructive feedback for our tutorial authors, please send us your feedback!