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trouble with passkey using Bluesmirf Gold and Picaxe

I recently received a Bluesmirf Gold module from little bird electronics and am struggling to connect the Picaxe to Pc using bluetooth. when i open the bluetooth icon in the taskbar and press "add" it finds a device named "FireFly-16FF" i am asuming this is the bluesmirf module.. i stabilise a connection with the option "no-passkey" selected and everything seems fine. the module is wired up to the picaxe Serial in and serial out pins and i am using the serrxd command. when i connected the device to pc it said output port is COM9, so i wrote some code to turn an LED on and off using serrxd and opened the Parallax Serial terminal. when i tried to enable a connection with COM9 a pop-up appeared asking for a passkey. whatever i enter the computer says "Windows was unable to exchange passkeys with the device because the user has not been authenticated. The operation being requested was not performed because the user has not been authenticated." 

would anyone know why i cant get communications working?

any help would be greatly appreciated

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The default passkey is provided in the advanced user manual for the RN-41 Bluetooth module.

I can run down all the one's I have seen though. First off, there should have been a pass key check during the pairing. It will be either 1234 or 0000. From there, it is almost always a baud rate issue. As a matter of fact, I have never had any problem that was not either a baud rate problem or having the RX/TX crossed. Double check the rate at which the bluesmirf is set at (it is probably 115,200 out of the box) and be sure your terminal is set to that rate.

Along those lines, you are going to have another issue if it is indeed still set at that default of 115,200 --its the fact that the picaxe is never going to get anywhere close to that speed. I can't remember the default rate for the sertxd/rxd commands but I sorta remember it at 2400. You may have a better shot using the Hser pins and the Hserin/out commands. 

Thanks Chris,

the passkey was indeed 1234. now on the bluesmirf i have a constant green where as before i only had flashing red. i'm assuming this means a connection is up and i should be able to transfer serial data.

I'm a little confused with all this baud rate stuff?!  what rate should i set the terminal on my pc to and what hz speed on the PICAXE?

oh and also what are the rts-0 and cts-i pins for on the bluesmirf?

sorry about all the questions but i am quite a beginner with these things


I'm thinking it may also be my code or setup. i have the picaxe and bluesmirf wired to the same 5v power supply and the tx to serial in and rx to serial out on the picaxe, i also have an led wired to pin b.3 and ground>


this is my code:


serrxd b1

select case b1


case "a"

high b.3

pause 500

goto main


case "b"

low b.3

pause 500

goto main

end select

goto main


Is there anything wrong with the code or setup?

Steady green light --that is very good. At this point, you have a baud rate issue.

Whenever you talk using a serial connection, that comunication must be done at a certain speed (baud rate). The terminal, the bluesmirf and the picaxe must all be using the same baud rate. As I said above, when you use the sertxd and serrxd commands you have to use the default rate (again, not sure but I think it is 2400). You can use these pins (and commands) but you will need to look up what the default rate is and set the terminal and BT unit to this speed. If you end up using the Hser pins and the hserin/ hserout pins you can use different baud rates on the picaxe but this still does not get away from the fact that you are going to have to adjust the baud rate on the bluesmirf either way. I really gotta suggest that you use the Hser pins in that the "regular" serial pins on a picaxe use an inverted signal which may turn out to be yet another problem down the road. Using the Hser pins, you can adjust this true/inverted signal.

The good news is that adjusting the BT unit will not be that bad and can be done with a FTDI board or via the BT itself and can be done via your terminal program. I did a video about this (at least doing it the FTDI way) which should point you in the right direction.




thankyou chris, after A LOT of fiddling with different baud rates on the pc BLuesmirf and picaxe i finally got it working.

oh and by the way i used the configuration method over bluetooth not using the FTDI board


You know, I have tried to configure over the BT connection a million times...   ...never got it to work.

At any rate, congrats. I have fought these kinda things a lot in the past --feels good when it works, my friend.