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Possible to use multiple bluetooth modules with 1 master/many slaves?


#1

I don’t have much experience to program with bluetooth, but if using for example this gadgeteer Bluetooth module
https://www.ghielectronics.com/catalog/product/312

Imagine a scenario with 6 microcontrollers ( like a cerberus, G120) to talk to each other.
For example:
1 master (G120) with a bluetooth adapter
5 slaves (Cerberus) and each have a bluetooth adapter.
The master would be the one sending the commands periodically to each slaves.

Would it be possible ? Or those adapters only work 1-1 communication ?


#2

Ok just to clarify:
For my application, its ok if I have to poll each of them back to back.
But do you think I could I achieve at least 1 acquisition of less than 1kbyte of data from 5 different bluetooth modules, per second?
Thanks for the help.


#3

What you’re trying to build is called a Wireless Sensor Network (WSN), and Bluetooth is not designed for that – and even if it were, there are smaller protocols that are lighter-weight and easier to work with.

The XBee modules are used almost universally by the hobbyist market for the sort of stuff you’re trying to do. Series 1 modules are basically “wireless serial” links, which won’t be very useful to you, while Series 2 devices offer more useful mesh networking support (including support for access points, routers, and end devices).

An XBee Series 2 set-up would be perfect for what you’re trying to achieve – you’d have your “master” hooked up with a S2 XBee programmed as an AP. All of your slave devices would be interfaced with S2 XBees programmed as end devices. Once they associated with the master, the master would be able to send messages to them individually, or to a broadcast address that they could all listen to. The XBee device takes care of the MAC and ZigBee stack, so you don’t need to worry about implementing that.


#4

An even better solution is few of the below :wink:


#5

lol


#6

@ Justin Love the new avatar!


#7

Techinally, yes, one bluetooth master can connect to seven slaves, at the same time.

But this is not supported on simple serial profile master modules.

To get that functionality you will need to use n HCI(i think) module that does nothing except the ratio stuff. Then you will have to implement the serial stack in software. Although this should be doable, it will require indepth knowledge of all things bluetooth.

BTW, I think it was Skeworks, but someone used an HCI module to talk to a PS3 controller, writing the stack in code. So it should be doable, with aformentioned knowledge…


#8

@ andre.m - My offer is a simple 9600 serial link - one to one or one to many etc.
Simple serial in one end - out the other - no config necessary - Simple :slight_smile:


#9

@ andre.m - 2.4, 500 feet, yes, no - cheaper than xbee


#10

Justin I’m curious, do you have a link explaining what your Gadgeteer board will do ?


#11

@ PhilM - watch the vid, its a shameless borrowing of their idea :smiley:

http://www.opensourcerf.com/rfd21815-wireless-inventors-shield-for-arduino.html