Multiple connections via bluetooth

Projects General Guidance
1

So for my project, I want three different Arduinos:
One Mega for the main controller
and two pro minis as sub controllers.

I want them all to connect to the mega via bluetooth
I have this for the mega:

And two of these for the minis:
http://www.amazon.com/gp/product/B00DQ4A7O6/ref=oh_details_o08_s00_i00?ie=UTF8&psc=1

I want to connect to both the minis to both send and receive data. From what I can find out, it seems I can only have one connection at a time. So I'm thinking of quickly connecting back and forth just long enough to send/receive data from that sub controller. Is there a library out there to make this easier or a tutorial to help me do it myself? Most of the things I'm finding seem to be out of date and don't work for various reasons.

Thanks

2

Hi,

I'm struggling with same idea/problem. You are saying "From what I can find out, it seems I can only have one connection at a time. ". How did you find this out?

My problem is this:

raspberry with usb/BT-dongle
arduino mega with HC-05 BT module
arduino micro with HC-05 BT module

I want to connect arduinos to rasp so I that they send data to raspberry simultaneously. I can get them connected one at the time:

*root@raspberrypi:~# bt-device -l *
Added devices:
HCBLU (00:14:01:xx:xx:92)
root@raspberrypi:~# rfcomm -a
rfcomm0: 00:14:01:xx:xx:92 channel 1 clean

This runs a small software, which just echoes everything back and it works ok. When I try to add another arduino:

root@raspberrypi:~# echo "2000" | bt-device -c 00:14:01:xx:xx:89
Connecting to: 00:14:01:xx:xx:89
Agent registered
Device: muovi (00:14:01:xx:xx:89)
Enter PIN code: Agent released
Done
root@raspberrypi:~# bt-device -l
Added devices:
HCBLU (00:14:01:xx:xx:92)
muovi (00:14:01:xx:xx:89)
root@raspberrypi:~# rfcomm bind hci0 00:14:01:xx:xx:89 2
Can't create device: Address already in use

I have both BT's in /etc/bluetooth/rfcomm.conf and can get rfcomm to complete:

root@raspberrypi:~# rfcomm bind all
root@raspberrypi:~# rfcomm -a
rfcomm1: 00:14:01:xx:xx:92 channel 2 clean
rfcomm2: 00:14:01:xx:xx:89 channel 1 clean

but as soon as I try to access them with minicom or screen:

root@raspberrypi:~# minicom
minicom: cannot open /dev/rfcomm1: Connection refused
root@raspberrypi:~# rfcomm -a
rfcomm1: 00:14:01:xx:xx:92 channel 2 closed
rfcomm2: 00:14:01:xx:xx:89 channel 1 clean

So how could we use two at the same time? Any help appreciated!

-Proge

3

Answering to myself, need to use rfcomm connect, after that I can talk to two bt-devices at the same time..

-Proge