Bluetooth connectivity

[max@birley_com]

I have purchased a android phone and I can see the Bluetooth devise and I can connect to it
The bT device has a micro push button however it has a EN connection not a KEY connection. The BT device (HC-05) is connected to the RX2 TX2 pins on the mega through a bi directional voltage logic circuit so not to blow the device. I can get the BT device to blink slowly ie on for 2 seconds and off for 2 seconds (ie in AT programming mode) or I can get it to blink fast say 2 flashes per second (looking for connection mode)
The problem is I can not get it connected when I run the communication option 3 the 2. It always fails.
I have undertaken some limited at programming using an ftdi adaptor so I know most things are working however I still can not get the device to connect to the mega.
I have followed the new instructions as closely as I can.
Any suggestions

 

[nero76]

I think the EN pin has to stay unconnected. The key pin is the same as the micro push button. The AT mode is the correct one for programming the bluetooth module. For a quick test, you could also try without level shifter, maybe the level shifter is the problem.

 

[max@birley_com]

If I get rid of the level shifter will I damage the bluetooth unit? On my BT unit by the RX TX pins it has written LEVEL:3.3V therefore I am concerned about 5V from the mega
Also when I connect this board to the FTDI and program only has access to some AT commands. This iindicating that I Not in the full AT programming mode.

So that your test works how must the BT module be programmed
Mode slave or master
Pasword 1234
Baud 19200
Name can it be anything ?
Etc
Etc
Regards
Max

Regards

 

[nero76]

The bluetooth settings should be : slave, password anything, baud 19200, name anything

 

[max@birley_com]

What about the 5V verse 3.3v?

 

[nero76]

For a quick test it should work (to find out if the level shifter is the problem) - I have never had any issues without, however it's not recommended as permanent solution (the transistors at the I/O pins are sort of robust to overvoltage to some degree and time). And it's really really recommended to use the PCB, so these types of errors are gone.

 

[max@birley_com]

I am making the PCB however I want to progress with the Mini so I learn the software. I removed the logic level shifter and this time I also held the micro button down during the test and the communications test worked successfully.
On my android I am using the downloaded app ArduRomote. It is pair to the BT device on the megga however it only gives me 2 options
Choose paid BT devise
1. Mini ie the name of the BT device. When I press it makes a noise and flashes orange..but then nothing or
2. BT config> this option makes a bing noise and flashes but goes nowhere

The BT flashes twice quickly every 2 seconds

So I seem stuck again

What next?

 

[nero76]

Try to re-power the module. I think it's important and have updated that on the Wiki right now too...

 

[max@birley_com]

When I press mini on the android in the serial monitor the following is printed
Pfod cmd= 983:35:71:02:0F

When I press BT confit I get in the monitor just
Pfod cmd=

So the ArduRemote is connected to the robot however I do not get any other screens to see parameters or control the robot

Have I missed a download or something

Regards
Max

 

[nero76]

The commands sent from the Android App to the PC shown in the serial console should look like this:

Pfod cmd= {.}

The cmd you received looks odd - I assume you already tried to re-power the module (to leave AT mode).

 

[max@birley_com]

I just re installed the arduRemote on the android and the menu appeared.

Great it looks like what I wanted is working. I will have a play and get back to you

LESSONS
Micro button needs pressing on the BT when doing the communication test
And need to download Ardumower after the communication test

Thanks max

 

[max@birley_com]

I would like to thank everybody that responded to my requests for help. My mini is working with bluetooth.I now need to add some other stuff , sonar imu odimeter etc and make the transition to the PCB-3.
Once again this is a great project especially when I make a break through and everything works as it should
Thanks agian
Max

 

[nero76]

You're welcome. We are trying hard to make everything easier (documentation, code), however it's not always easy as everyone has different starting skills - hopefully more people can help us (documentation, code) to make this project easier in future. Everyone is invited .