Owner manual
usb-nSTEP Instructions 
Copyright Rigel Systems 2010  Page 2 of 4  www.rigelsys.com 
5)  Accept license agreement and proceed 
6)  Go Go to http://www.astrogene1000.com/products/gcusb_nstep/gcusb_nstep.htm 
7)  Download and save the “INF file, no code added” zip file, then double click the zip file to unzip. 
8)  Open the folder where the GCUSB_nSTEP executable is installed (left side of image below), and 
drag the “gc_usb_nSTEP1” setup information and security catalog files into it. . REMEMBER the 
directory in case you in step 10 you need to point the Device Manager explicitly to the directory. 
9)  Plug the usb-nSTEP hardware into a USB port and device drive should install. If it doesn’ then 
follow step 10. 
10)  Open Device Manager, click on Other Devices, click on USB nSTEP device, pick Driver tab and 
select Update Driver. On next screen, select “browse local disk” and let it go to town! 
11)  Driver is installed  so select Close. 
12)  Select PORTS (COM & LPT) in the Device Manager. USB to focus stepper controller (COM#) 
is displayed, with COM port assigned. You will need to know this COM port to setup the GCUSB-
nSTEP application. You must change the COM port assignment by clicking on the USB to focus 
stepper controller, select the Port Settings tab, select Advanced and selecting a “virgin” COM 
Port Number (one that doesn’t say “in use”) to avoid problems with settings from other 
applications. For backwards compatibility, values are 1-16. 
13)  Ready to go  Use the shortcut on your desktop to activate the GCUSB-nSTEP application. 
Tips on Connecting to FocusMax 
Usb-nSTEP is ascom compatible and can be interfaced to FocusMax. Note: FocusMax is not our 
software. FocusMax is a freeware program written by LARRY WEBER and STEVE BRADY for use with 
commercial telescope focusing devices used by amateur astronomers. FocusMax can be downloaded 
from the FMaxUG on Yahoo Groups. Below are tips to help interface to FocusMax.  
1)  Make sure your windows account has ADMIN privileges. 
2)  Join the Yahoo FMaxUG, Download and install the latest version of FocusMax (3.5.0 as of this 
writing). Start FocusMax. If it doesn’t start and produces an error message about log files, then 
you need to create the directories that it’s expecting for data, image, and log files.  Open the 
FocusMax HELP file which talks about the directories, they may not be where help file states.  Run 
the ASCOM PROFILER and under focuser, select FocusMax and read the profile file. In it you will 
find where FocusMax thinks the directories are.  Go to those locations and create the data, image 
and log file directories. Then you should be able to start FocusMax and inside of FocusMax 
change the path to where you really want those directories.  Any problems, ask the FMaxUG. 
3)  Right click on the gcusb_nFOCUS shortcut and check the properties / compatibility tab and make 
sure the "run in compatibility ..." and "run with admin..." check boxes are NOT checked. 
4)  Start the gcusb_nFOCUS application, plug in the gcusb_nfocus hardware, and “connect” to the 
hardware. Run CIN/COUT to move motor to confirm hardware is working. Minimize the 
gcusb_nfocus app to the dock. 
5)  Right click FocusMax shortcut and check properties/compatibility tab and and make sure the "run 
in compatibility ..." and "run with admin..."check boxes are NOT checked. 
6)  Start FocusMax and pick the system tab, select gcusb_nFOCUS and connect.  
7)  Select the focuser tab. Correct focus position and temperature should be displayed.  Maximize the 
gcusb_nFOCUS app from the dock and compare to its value. 
8)  Click on  "jog" at the top of the FocusMax focuser tab and jog the motor in/out to verify FocusMax 
is working with nfocus. 
9)  Ready to go 




