Bluetooth notes for Debian/ Linux

CS // 5 Mar 2012 // Comments Off on Bluetooth notes for Debian/ Linux

Some reminder notes for myself for playing around with Bluetooth adaptors.

Note that bluetooth seems to be incredibly flaky – at least from my tests.
I would often get timeouts and failures. Results will depend on the radio environment around you…
Plus apparently the bluetooth adaptors I have all have the same mac address, so thats also an issue if you encounter the same and have > 1 plugged into various computers… Oh well, at least they were cheap!

Did some post mortem testing with a T series Thinkpad, seemed better, but still not 100% – I guess thats why people just don’t use it.

Install bluetooth –

apt-get install bluez-utils bluetooth

plug in a usb bluetooth adaptor
reboot

This will install some useful bluetooth tools.
hcitool, hciconfig, rfcomm are the basic command line bluetooth tools we’ll be using.

Hopefully at this point your device is recognized –

hcitool dev

This should return the mac address of the bluetooth adaptor:

# hcitool dev
Devices:
hci0 00:1F:81:00:08:30

If the address is 00:00:00:00:00:00, then its not setup, check dmesg and see what kind of device you have.

Heres mine –

lsusb
Bus 001 Device 003: ID 0a12:0001 Cambridge Silicon Radio, Ltd Bluetooth Dongle (HCI mode)


And a grep of ooth (as could be BlueTooth or Bluetooth or bluetooth…) from dmesg


dmesg | grep ooth
[ 4.845001] Bluetooth: Core ver 2.15
[ 4.845130] Bluetooth: HCI device and connection manager initialized
[ 4.845132] Bluetooth: HCI socket layer initialized
[ 4.891477] Bluetooth: Generic Bluetooth USB driver ver 0.6
[ 8.940263] Bluetooth: L2CAP ver 2.14
[ 8.940264] Bluetooth: L2CAP socket layer initialized
[ 8.943819] Bluetooth: RFCOMM TTY layer initialized
[ 8.943822] Bluetooth: RFCOMM socket layer initialized
[ 8.943823] Bluetooth: RFCOMM ver 1.11
[ 8.990134] Bluetooth: BNEP (Ethernet Emulation) ver 1.3
[ 8.990135] Bluetooth: BNEP filters: protocol multicast
[ 9.298370] Bluetooth: SCO (Voice Link) ver 0.6
[ 9.298372] Bluetooth: SCO socket layer initialized


If you don’t get a valid mac address, reboot, as that seemed to work for me.
Yes, its a hassle, but I didn’t delve too deeply into what modules needed to load.
If you don’t want to reboot I’ve modprobed for bluetooth and have the modules below post boot

You can try loading those with modprobe

lsmod | grep bluetooth
bluetooth 41827 9 sco,bnep,rfcomm,l2cap,btusb
rfkill 13044 2 bluetooth


You can also use hciconfig to list the name of the device (this is what you’ll see listed in another device if you enable discovery…)

hciconfig -a name
hci0: Type: BR/EDR Bus: USB
BD Address: 00:1F:81:00:08:30 ACL MTU: 1021:4 SCO MTU: 180:1
UP RUNNING PSCAN ISCAN
RX bytes:3551 acl:52 sco:0 events:140 errors:0
TX bytes:1243 acl:50 sco:0 commands:53 errors:7
Features: 0xff 0x3e 0x09 0x76 0x80 0x01 0x00 0x80
Packet type: DM1 DM3 DM5 DH1 DH3 DH5 HV1 HV2 HV3
Link policy: RSWITCH HOLD SNIFF PARK
Link mode: SLAVE ACCEPT
Name: 'Accel-OB2'
Class: 0x000000
Service Classes: Unspecified
Device Class: Miscellaneous,
HCI Version: 2.0 (0x3) Revision: 0x44
LMP Version: 2.0 (0x3) Subversion: 0x3
Manufacturer: Cambridge Silicon Radio (10)


Assuming the above is working, hcitool dev gives you a mac address, then hcitool scan should give a list of nearby bluetooth devices.
Suggest make something discoverable – eg a closeby desktop with bluetooth for testing.

hcitool scan
Scanning ...
00:1E:52:EC:A5:50 apple’s iMac


As you can see I have a device close by
Lets get some info about it

# hcitool info 00:1E:52:EC:A5:50
Requesting information ...
BD Address: 00:1E:52:EC:A5:50
Device Name: apple’s iMac
LMP Version: 2.0 (0x3) LMP Subversion: 0x7ad
Manufacturer: Cambridge Silicon Radio (10)
Features: 0xff 0xff 0x8f 0xfe 0x9b 0xf9 0x00 0x80
<3-slot packets> <5-slot packets>





<3-slot EDR ACL> <5-slot EDR ACL>

<3-slot EDR eSCO>


Ping it

l2ping 00:1E:52:EC:A5:50

Ping: 00:1E:52:EC:A5:50 from 00:1F:81:00:08:30 (data size 44) ...
44 bytes from 00:1E:52:EC:A5:50 id 0 time 17.76ms
44 bytes from 00:1E:52:EC:A5:50 id 1 time 31.87ms
44 bytes from 00:1E:52:EC:A5:50 id 2 time 23.92ms


Lets try to connect to it


hcitool cc 00:1E:52:EC:A5:50
hcitool auth 00:1E:52:EC:A5:50


– For auth to work, you’ll need to setup a pincode file in /var/lib/bluetooth/[mac address of the bluetooth adaptor inside your computer]/pincodes
Add the mac address of the device you want to connect to, and the pincode e.g.

cat /var/lib/bluetooth/00:1F:81:00:08:30/pincodes

#mac address of device connecting to, pin to use when connecting
00:1E:52:EC:A5:50 0000

If you want to be able to see your computer from another device, make it visible –
Make our computer visible to a bluetooth scan
hciconfig hci0 piscan

We can also setup a serial connection to our bluetooth device we want to connect to
rfcomm sets up a virtual serial port connection on the hci port specified. Then you can access the device via a serial connection – eg for gnokii or similar.

rfcomm connect 0 00:1E:52:EC:A5:50

Assuming you’ve connected to the device, and setup an rfcomm serial connection, you can use gnokii to query the device.
Gnokii is mostly for Nokia phones, but you can use AT commands to connect to other devices, such as iPhones etc.
For my test purposes, I needed to assist with integrating SMS to PHP, so was looking at setting up a bluetooth connection to a phone, then querying that for sms’s every 30 seconds or so, then passing that to a db or php script. Gnokii was the second part of that equation, as it can do some of that without too much headache.

(in gnokii – get the phone details)
gnokii --shell 2> /dev/null

#(in gnokii - get the first sms in the phone)
> --getsms IN 1