Resolved Error 27 when trying to connect to ST-i

Discussion in 'Specialty Cameras SG-4, AllSky, ST-I' started by Pieter Strauss, Sep 17, 2018.

  1. Pieter Strauss

    Pieter Strauss Cyanogen Customer

    Joined:
    Nov 3, 2014
    Messages:
    36
    I moved the USB cable to another port on my PC, and am now not able to connect to my ST-i camera.
    PC is Win7, I moved the cable to a port on another USB hub, got the Windows is looking for a driver msg, let it look, came back and got message driver and firmware installed. Tried to connect with PHD2 program (worked fine two days ago), got error 27. Bounced windows, no fix. When Win 7 is coming up it hits the ST-i and exercises its shutter.
    Moved cable back to original port. Bounced windows. Tried to access with PHD2, same error. Tried to access ST-i with MxmDL, error 27. Hmm.

    So, what to do? MxmDL is latest version, and drivers were refreshed in the last 2 months. (Tried to update, but internet access is spotty in my observatory.)

    PS one thing I can think of: my LX200 was not powered on. The ST-i is directly connected to the LX200 in order to guide it. Is this what error 27 means?
     
  2. Doug

    Doug Staff Member

    Joined:
    Sep 25, 2014
    Messages:
    7,291
    Error 27 means "Device Not Found".

    Check the Windows Device Manager to see if the camera is correctly identified as an SBIG camera. It should show as "SBIG USB Devices", and under that "SBIG USB Camera with Firmware".

    If that doesn't work then either the drivers aren't installed correctly (SBIG Driver Checker) or the camera isn't connecting to the PC for some reason.

    Please note that the USB cable that comes with the camera is NOT just an ordinary cable. It has extra large power wiring. The ST-I consumes enough power that this is necessary when using a long cable. If you grabbed a random long cable then it might not work correctly.
     
  3. Pieter Strauss

    Pieter Strauss Cyanogen Customer

    Joined:
    Nov 3, 2014
    Messages:
    36
    Many thanks, problem solved, though unclear how.
    The device showed up in Device Manager as expected.
    The USB cable is the same one -- just switched USB ports.
    The difference this time was: I connected the 8300 to power first (in my earlier activities it remained powered off the whole time), listened to Win 7 talk to it, started Mxm, connected to the 8300, then plugged in the ST-i, noted its light was lit, started PHD2 and connected to it. No worries.
    I had noticed when running PHD (1) that there was some dependency on which device was started first, but since using PHD2 I had not seen this.
    At any rate, thanks for your help.
    PS did manage to run Driverchecker, and it informed me I was current on all drivers.

    --Pieter Strauss
     
  4. Doug

    Doug Staff Member

    Joined:
    Sep 25, 2014
    Messages:
    7,291
    Okay this is probably a PHD quirk. It is probably getting confused between "camera 1" and "camera 2".

    When the computer powers up, it always scans the USB bus in the same order. The first SBIG camera it finds is assigned "camera 1", the second "camera 2" and so on. If you move one of the cameras to a different port it may end up swapping which camera is "camera 1" and "camera 2". In that case the PHD software might not be able to find it.

    By plugging in powered-up cameras in a particular order, you force the first one to be plugged in to be "camera 1". This overrides the computer scanning the bus at power-up.

    If you want to avoid manually connecting the cameras each time, simply swapping their plugs will cause them to be scanned in the opposite order.
     
  5. Pieter Strauss

    Pieter Strauss Cyanogen Customer

    Joined:
    Nov 3, 2014
    Messages:
    36



    Exactly what I needed to know! Many thanks.
     

Share This Page