Cannot communicate with BT board version 1.06 after changing baud rate.

Using Arduino Networking, Protocols, and Devices
1

Hello,

I connected to the Bt board fine at the default 9600 baud rate, and I received "OK"
I then typed in command AT+BAUD7 and now I cannot reconnect at any baud rate?

I a real newbie at this.

Thanks in advance for any help.

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You have to put it back into communication mode. With my BT module, AT+RESET

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Thank you for response, but when I send command AT+RESET I do not get any feedback, I do not even know what baud rate it is at to communicate with the board.

4

"BT board version 1.06" is not a description of a bluetooth module, it is simply a description of the board to which the bluetooth module is attached. Since you talk about AT+BAUD7, I assume you are using an HC-06 device.

If you indeed set the baud rate and received an OK57600, I guess that proves that it is an HC-06 and there is nothing actually wrong with it. Your problem is most likely that you are using software serial and at too high a speed. I bet you don't have a good reason to use software serial at all but, in the unlikely event that you do, you can set the baud rate to BAUD4, and it will probably be OK. Alternatively, you might use the device on hardware serial and it may be OK at 57600 as it is set. In that event, I bet you don't have good reason to run it at 57600 either, and you might as well do a proper job and set BAUD8.

AT+RESET is an invalid command with HC-06. If you want to communicate, just communicate.

The AT commands are sent at 9600, irrespective of the communication baud rate.

5

Thanks for your help, but below is the image of what I have I am pretty sure it's a HC-06?

960×520 51.8 KB

Also, I do need 57600 for the app I am trying to use. At least, that is what I have been told.

6

Yes it is an HC-06, the four pins confirm that.
Being "told" to use 57600 is not much to go on.
Much more important is: are you using software serial? Please don't tell me that whoever told you to use 57600 also told you to use software serial. It might be time to be more forthcoming with your code, and what you want to do. As I said, if HC-06 said OK when you set it to 57600, there is probably nothing wrong with it.

7

Thanks Nick for your help. I honestly am a real newbie at this and not working on code, all I am trying to do is set the baud rate to 57600 with an FTDI cable using Adruino software. I need the baud rate because the telemetry module that I am connecting to the BT HC-06, (I'm told) needs 57600 to communicate with the app. So far I thought I did everything correct, but I now cannot get feedback from Adruino to confirm the baud rate. Also, it is not connecting with the app. I have no clue at what baud rate it is at, but it is pairing with my Galaxy Tab, Win 7 computer but not with Blackberry phone, but that 's as far as I can get and it will not work with apps. Sorry if I'm on the wrong forum but this is the only one that I thought could help. The worst I'll be off is the cost of the BT module, so no real deal, just don't want it to happen if I try again.

8

OK, as I understand it, the objective is to use the HC-06 with an unknown telemetry device that has serial output at 57600, not an Arduino, you can't change the rate on the telemetry device, and you are only using Arduino to configure the HC-06 to suit.If this is correct, and the unknown device is just some dumb data transmitter, I think the HC-06 should be fine and all your troubles may be at the other end.

Be aware that HC-06 has two quite separate functions

  1. Bluetooth comms by wireless. To the phone
    This is done by bluetooth protocols and not configurable by you.

  2. Serial comms by wire. To Arduino or other device
    This is configurable by you, but the default settings usually suffice, and all you need to know is what they are.

The "pairing" falls into category 1. above, Arduino has nothing to do with the operation, all it does is provide power. The Galaxy and PC suggest all is kosher with HC-06, and the Blackberry is suss.

tywon_on:
that 's as far as I can get and it will not work with apps.

This is unintelligible, and what apps anyway? I suggest you stick with the Galaxy and run a bluetooth terminal. The terminal makes the connection to HC-06 and, when is it successful, it will tell you, and the LED on HC-06 stops flashing. Have you got that far?

9

Yes it does stop flashing, the app is Tower and also tried Droid Planner. With both the light stops flashing but the apps says no connection.

10

I'm afraid I am running out of ideas. If the LED stops flashing, it should be an indication of successful connection. Even if the baud rate is wrong, that is merely between Arduino and BT, and I don't think it has any bearing on the wireless connection. The Android apps are meaningless to me and I think you should test this with a standard terminal, but all apps should connect in the same way, i.e. you make the connection manually, and the LED stops flashing.

11

Nick, thanks for all your help.

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