The last time I tried my Bluetooth adapter was after I remade it. I encountered that error and left it at that for the time being, assuming I made a mistake. But perhaps there is a bug?

Hi Ilhoujin,

Thanks for responding! Are you also using the Shoestring BT Adapter? If I may ask, in one of your previous posts you were suggesting to add a 1 and the & behind the MAC address, -what is the purpose of the „1“?

Anyway, sounds like your solution was working, but not anymore - so it might really be a sort of „bug“.

Best, Helge

Well I can't be sure if my problem was hardware or software because I rebuilt the device, and encountered frustrations.
I don't recall the full syntax reasoning for the 1. But the trailing & is required to allow the Pi to continue to complete the boot, because commands in rc.local are run at boot time and will hang on them while waiting.

In my case problem was Blueman . It was auto connecting the device on boot. So I made sure on reboot it wasn't auto connecting. Blueman was used only once to pair the device .

Now I run this below script after Login

sudo rfcomm bind hci0 <your mac address> 1
sleep 5
sudo chown <username> /dev/rfcomm0

also to note when i put the above script to invoke from my rc.local device wasnt wasn't connecting to mount ;that is something i need to investigate further. Hope this helps.

My guess as to why it didn't work in rc.local is the absence of the trailing & character

When just capturing the script line by line into the terminal, it works - which is a big relief!

But same is not working just from the rc.local.

Would anyone happen to know how binding Bluetooth upon start up? Tried including the commands (bind, chown) in rc.local, but that does not work, just via terminal commands.

Or should I save script as a program and invoke via launcher?

I would also like to see Bluetooth support for the rpi3 under Stellarmate and Astroberry. I have a Tak EM-200 and could use one of these adapters:
www.kanda.com/products/Sena/PARANI-SD1000-00.html#desc

I just got around to reassembling my BT adapter. Curious things happened. Initially I had difficulty connecting, it turned out to be bluetooth manager taking taking ownership of the device. You can check for thisTake the ID numberThis will tell you what is using the /dev/rfcomm0. And is behind the failure to connect to port errors.
So this trick is to manually bind the device, but not connect to it. It appears to connect automatically when the mount driver is initiated.

At this stage I was making a connection, but it randomly would disconnect giving a TTY read write error when a command was given. I tried some of the other advice given, and that stopped happening, but now all inputs I give trigger a yellow light in the INDI console and does nothing.
Oddly enough one time it behaved itself. But failed after a simple restart of the INDI server.

I just did a fresh install of Astroberry Server, and I've found that Bluetooth works without a hitch when manually bound. But something later broke it after updating the system.

After performing a normal update, EQMod continues to work with my HC-05 bluetooth mount interface.
It is something applied during a dist-upgrade which introduced connection issues. It has to be related to one of these upgrades.
If I had to choose, I would place blame on modemmanager. As I have come across that mentioned elsewhere in relation to bluetooth issues.

OK. Upgraded Modemmanager is definitely involved. Although I do not have a full understanding as to its purpose, I decided to remove the program in its entirety. After rebooting, EQMod was once again communicating with the mount through Bluetooth.

With a little sleuthing I found this. Modemmanager appears to send "AT-GCAP" data and put it in an unstable state. There are a few work arounds provided. I might try the udev rules exception method described in the thread.
ubuntuforums.org/showthread.php?t=2056285