I have had the same problem with a USB interface as well as over a Bluetooth adapter I've made.

Hi,
I had the same problem, Usb - Direct to Eq6. Ekos connect but finish with tty error.

Attach Ekos log maybe can help,

Hardware is working ok, no poblem with Win eqmod

Thanks in advance
Jordi

no log is attached.

Sorry

Attached again

Thanks in advance

I use my Skywatcher Virtuoso mount with handmade serial-to-USB or bluetooth cable to connect with a RPi3. My experiences:

- The Bluetooth is not reliable enough to work with INDI. I think this is a general HW issue. You really have to find Bluetooth components with trial-and-error which work 100% reliable together.
- My wired cable keeps disconnecting and reconnecting the serial line after a few hours. Most likely because of the cheap USB-to-serial HW from ebay which most likely a fake Chinese counterfeit replica.

I think the connection problems are mostly likely related to HW all the time, not much to do on INDI side.

I am having this issue too with EQMOD using a pluszmis BT adapter on RPI3. Sometimes is retrieves those messages and can't connect to mount.
It looks like the generated comm port (rfcomm0) is always busy with some process and it's not free to accept a connection. if I insist on connection it
eventually connects. I think this is related to some kind of timeout reading data from the com port. Once it's connected it's pretty rock solid.

I would suggest a timeout / reconnect option, that would be great too and it would solve some problems, not only on EQMOD but also on other drivers where connections are not established on the first time. Using the new option to SEARCH for Comm Ports solves the issue most of the time. When I am really stuck, killing and restarting the server also seems to solve it. I don't know if this really the same issue as reported.

As you can see in the first time it tries to connect it fails, the second time, it does connect correctly:

2017-04-04T19:48:04.329 - DEBG - EQMod Mount : "Error: -> tty read failed, check connection: Timeout error "
2017-04-04T19:48:04.371 - DEBG - Ekos: EQMod Mount is disconnected.
2017-04-04T19:48:04.372 - DEBG - Ekos: "EQMod Mount is disconnected."
2017-04-04T19:48:15.565 - DEBG - Ekos: "Connecting INDI devices..."
2017-04-04T19:48:15.672 - DEBG - EQMod Mount : "Successfully connected to EQMod Mount. "
2017-04-04T19:48:15.676 - DEBG - EQMod Mount : "EQMod Mount is online. "

nmac:
To the file /etc/rc.local add the line:With Bluetooth adapter's MAC address in place of the X's
This will automatically reserve rfcomm0 for that device at startup.

Hi thanks, that's what I was doing before, but the adapter would not respond.
I'll try again.

The trailing '&' is key

Ohhh right, I think i missed that. Thanks

EDIT: That still does not work on mine I can only make a bluetooth connection after the full boot.
I think at early stages of boot, drivers are not yet fully loaded.

Hmm perhaps I misunderstood what you meant byIf that means as a secondary adapter to the one built into the Pi3, it's a completely different issue. My earlier comment was for connecting to an adapter from the Pi, where the adapter is connected to the mount as an EQMOD direct bluetooth interface.

If I can throw my own 2 cents, I had the same symptoms on an EQ-5, and it was definitely the cable which was not plugged securely enough. OK EQ-5 is using a RJ45 plug, but it appeared that even a small electrical disconnection during rotations was causing a desync in the tty exchanges, which only a disconnect/reconnect of the driver, thus a close/open of the device port, would solve. It is very tricky to diagnose physically actually. Currently the eqmod driver isn't covering that failure situation (fail exchange, try close/open).