Bluetooth LE on Raspbian

Question

I installed bluez-5.15 from source with the following configuration:

$ ./configure --prefix=/usr --mandir=/usr/share/man --sysconfdir=/etc \
--localstatedir=/var --libexecdir=/lib --disable-systemd

Then I had to copy gatttool manually into the /usr/local/bin dir

$ sudo cp attrib/gatttool /usr/local/bin/

I rebooted the Raspberry Pi and tried the following to connect to my BLE device:

$ sudo hciconfig hci0 up

$ sudo hcitool lescan
LE Scan ...  
EA:FB:B5:CE:B0:13 DfuTarg

$ sudo hcitool lewladd EA:FB:B5:CE:B0:13

$ sudo hcitool lecc EA:FB:B5:CE:B0:13
Could not create connection: Input/output error

So then I tried to connect with gatttool:

$ gatttool -b EA:FB:B5:CE:B0:13 --interactive
[EA:FB:B5:CE:B0:13][LE]> connect
Attempting to connect to EA:FB:B5:CE:B0:13
Error: connect error: Device or resource busy (16)
[EA:FB:B5:CE:B0:13][LE]>

What am I missing here - is this a configuration issue? What do the errors mean?

Answer 1

First off, I spoke with a colleague about my configuration and for Raspbian (or more specifically, Debian) he recommended the following configuration settings:

./configure --prefix=/usr --mandir=/usr/share/man --sysconfdir=/etc --localstatedir=/var --enable-library --with-systemdsystemunitdir=/lib/systemd/system --with-systemduserunitdir=/usr/lib/systemd

Afterward, upon further inspection, here is how I was able to successfully connect. So what was happening was that the device I was trying to connect to (an NRF-based BLE device) required the LE address flag to be set to 'random'. See below:

gatttool -t random -b EA:FB:B5:CE:B0:13 -I

Then the result:

[EA:FB:B5:CE:B0:13][LE]> connect
Attempting to connect to EA:FB:B5:CE:B0:13
Connection successful
[EA:FB:B5:CE:B0:13][LE]> characteristics
handle: 0x0002, char properties: 0x0a, char value handle: 0x0003, uuid: 00002a00
-0000-1000-8000-00805f9b34fb

Huzzah! Also, there may be a need to set the security level to something lower than high:

[EA:FB:B5:CE:B0:13][LE]> sec-level medium