SXFilterWheel can not connected


Hi, i am trying to connect the SX Filterwheel and the following error is appearing

Expception: the device is not connected
Module SXFW write/read failed using USB Outcomes Code 37-Wini Error.

However I can connect the FW when I press the connect symbol in the equipment section without a problem, but cannot move the filters , the NA symbol does not go green.

Another point about all this is that I do connect the FW in maxim dl.



This happens to me fairly frequently, I unplug/plug the USB connector on the wheel and SGP can then connect to it.


Yep - I had the same experience with both SX wheels and also using MDL too. I never completely stopped it happening but it did improve after a firmware update. In terms of USB connection reliability, I have found, in general, that one master power switch, with everything powering up at the same time, is more likely to give me issues than powering up devices progressively (in groups).


Yes - have experienced this issue as well with both my regular and “maxi” SX filter wheels. The problem is that device manager does not pick up the FW as a device. You can confirm by going to device manager and seeing an unidentified entry with yellow warning symbol. I believe this may be related to the “power up everything at one time” that @buzz mentions. This FW device manager problem happens for me every time I reboot the obsy PC.

The challenge with the proposed solution (unplug and replug usb cable) is with remote operation. One possible workaround is to go to the device manager and “dis-able” the device and then “enable” the device. Sometimes have to try this 2 or 3 times (or more) before it gets recognized properly. Always seemed to work for the regular SX FW but is hit-and-miss for the Maxi FW.

I suppose another option would be one of those remote controlled usb hubs that can power cycle the usb connection. But this would mean another device in the chain and extra cables etc (more things that can go wrong!).



I have a box of PSUs that supply the NUC, Camera/USB hub and everything else. It allows me to separate clean and dirty supplies and also switch them independently. I feed this into a steel box which houses all my modules, with fusing and toggle switches, as described in my book. I recently decided to add a 4-way USB controlled relay, for switching the DC power on and off to the culprits. I can reset my camera, mount (48V), focuser and an external port through an ASCOM driver I wrote. I then have a web controlled power relay to the NUC. I have them all set to ‘normally closed’ and can override that with a simple application. On the few occasions I have issues, a power reset normally works. If the USB itself gets confused, it normally requires a PC reboot, since the hub is drawing power from the NUC and turning the hub power power supply off does not reset it. The NUC is set up to boot up on power, so if I shut it down and turn off its power and then turn it back on, it does a full reboots of it and the USB system.


Hello folks, first post on this forum from a complete novice.

The short answer is that I found a solution to this problem - the USB port on my computer was USB 3, but the filter wheel (a few years old) was intended for USB 2. Plugging it into a USB 2 port fixed things, so - at least in my case - it was a speed issue.

The clues were there, but I didn’t see them until after a day of poking around. I had used the wheel without problem on my (8 year old) MBP without problems, and it was only when I bought an Eagle 2 computer that I hit this issue. Fortunately, the Eagle 2 has both USB 2 and USB 3 ports.


You maybe using an old driver.
The latest drivers are here
You will need the Ascom driver, control program, and firmware update 1042-AR for automatic reboot.