Wednesday, November 7, 2007, 1:52:12 PM, Arild wrote: I have two serial<->USB adaptors - I think I bought one from London Drigs, and one from The Source. A given USB port on my computer always appears as the same COM port, regardless of which adaptor is used in it, however they are COM4 and COM5. I think it may be possible to change the COM ports in Windows Device Manager, but as I can set my programs to use these ports, I haven't had a reason to try. AJ> REPLY AJ> I guess I should have mentioned but forgot. AJ> My compass deviation/calibration machine runs machine code. AJ> I think the old Toshiba ran DOS 3.2 but the program boots from the floppy AJ> and was written in C+ as a very tight fast machine language app. That may be a problem - but it might run in a DOS/CommandLine window in XP. I wrote an NMEA logger program for DOS some years ago - I'll have a try later tonight to see if it will work under XP. AJ> If I repackage the whole thing including the 400hz 26V gyro reference; the AJ> processor would be a gutted laptop buried inside the guts. It would boot AJ> from a BIOS chip specially programmed with this extra code added to the AJ> basic BIOS. The idea being the machine has to run from a 12V DC cigarette AJ> plug. AJ> I would not need a keyboard unless a lot of frills was added like the AJ> ability to generate a form wherein you enter Vessel Name, Owner, Date of AJ> check/calibration, and a dotted line for the compass adjustor to sign off. AJ> Only five keys are needed. ON OFF, STANDBY, LOG PRINT. AJ> But those are frills we didn't bother with when I designed this compass AJ> calibrator some 10 years ago. AJ> I'm not a programmer! A friend who happens to be rather good and who can AJ> write about 1000 lines of checked and verified code per day, knocked off AJ> this little program in less than a hour. There can't be more than a hundred AJ> or so line of code. It isn't Windoze code bloat. If you have the source code (or even if you don't, but have the specs or requirements) I may be able to produce a stand-alone box for you. AJ> REGARDS AJ> Arild -- Peter Bennett, VE7CEI Vancouver, B.C., Canada Ennos 31 "Honeycomb" GPS and NMEA info: http://vancouver-webpages.com/peter Vancouver Power Squadron: http://vancouver.powersquadron.ca