I have a CNC conversion milling machine. It was hooked to an old DOS 6.x computer and it worked fine. I have switched to a computer running Windows 98 and have problems. When I start the program in the DOS command window the software loads fine. The editor works fine.. all works fine until I try to run a machine (command machine motion). A message flashes that it can't find the pendant (a motion teaching device attatched to the CNC machine). Booting my computer to the Windows 98 boot diskette (just a dos window) and the program works fine. Any suggestions, folks? Thanks

Your DOS program is doing a direct I/O (Input/Output) operation to the hardware that is not supported by Windows. It might be possible to write a Windows VXD driver that can handle this, but that cost more than it is worth. You would be better off just running the diskette version if you can. You can setup the system to boot into DOS from the disk drive.

As your software is talking directly to the pendant, Windows is interfering wih the direct I/O. I suggest you configure your PC for dual boot with DOS as the OS to run for your CNC App.