Macintosh with Virtual PC Loads Garmin GPS receivers
that have a 9 pin SERIAL interface
How to make them communicate effectively

Rick Klain 

Here's a quick guide on how to get Garmin's software to work on and interface with their standard serial interface (NOT USB!) GPS devices on a Macintosh running Virtual PC.. In my case I am using a 12-inch, 1.33MHz G4 PowerBook, OS X  10.3.7, Microsoft Virtual PC 6.1.1 and Microsoft Windows XP Pro with all the latest updates (getting the Microsoft configured and updated takes a long time, and is probably impossible without a broadband connection to download all the updates). I also have a big hard disk (80 GB) and 1 GB of RAM, of which 512 MB was allocated to Windows. Disclaimer: if you're running a different configuration, you may have to discover your own solution. My configuration seems very solid and it takes no longer to download MapSource maps segments to the GPS than when using my Windows laptop (an HP 1.6 GHz Mobile), also running XP Pro. Here's what I call the "short list" on how to do this:

1. Make sure you're running the latest version of OS X and you've run the OS X "Disk Utility" and performed a "Repair Disk Permissions".

2. Make sure you've installed Virtual PC's latest updates (v. 6.1.1 at this time for G4's running OS X and a flavor of v. 7 for G5's). Also if you're running Windows XP Pro (which has the best driver support both built-in and otherwise), be sure you've updated with all the latest service packs and critical updates.

Note: all this may work with older Machines (G3 Macs), older OS's (including flavors of Mac OS 9.x); But.. I've got no experience with these...

3. You'll need to purchase a USB to Serial Converter. Suggest the Keyspan P/N USA-19HS, which you can get from GPS City.

4. Install the Keyspan USB Serial Software for OS X and turn to page 27 in their PDF manual, which describes in " - Virtual PC" how to configure a USB-to-serial port using Keyspan's included software (included on their CD). You'll need to use Keyspan's Serial Assistant for OS X to "discover" the attached Keyspan USB-to-serial hardware and note what name it gives this new serial port. This Keyspan application is used to create a COM1 serial port for virtual PC to use.

5. Launch VirtualPC and go to the "Settings" panel, usually found at the bottom of the "Edit" menu pull-down, as well as on the Virtual PC List window. Select the COM1 Port and under COM1 Port Settings (on the right) select "Mac serial port:" and you should be able to see the same name that Keyspan used under OS X. If you can't find the Keyspan port, you may have to also install the Keyspan Windows drivers and configure. But, be sure to re-boot before you try anything fancy -- this might solve the problem.

6. Be sure you're running the latest update of MapSource (currently v. 6.3) and you then should be able to find your Garmin GPS device. At this point you may want to also make sure that your Garmin GPS unit has the latest firmware installed.

7. You can also configure Windows XP Pro to run faster by doing at least two things that I did:

--A. Go into the "System" control panel and to the "Advanced" Tab. Click on "Settings" under "Performance" and choose "Adjust for best performance". This allocates more of the Mac's processor power to Windows.

--B. Disable the "Themes" service by: clicking on the control panel and then double-click on "Administrative Tools" , then double-click on "Services (shortcut)" which brings up the "Service (Local)" window and then select "Standard" tab at the bottom of this window, and then scroll down to and double-click on "Themes" and then  select "Status type: disabled",  then "Apply" and then "O.K." Whew!

Clearly, if you're not detail oriented, patient and persistent, you can just spend your time waiting around... for Windows...

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Here's what I'm doing with the GPS stuff. I've got two 2005 motorcycle trips planned in Europe (Sicily/Italy and then Ireland). I'll be taking along my Garmin GPS V and will be mounting it on the "rental" motorcycles that the tour company provides ( Since I'm only taking one computer along with me, mostly for handling digital photography and some "WiFi hotspot" and hotel DSL connectivity, and it's the Macintosh noted above, GPS map downloading was a secondary, but essential need. On these motorcycle trips we ride in small groups, where for the most part, the daily start and finish destinations are the only thing for sure. On some "layover" days, we're free to explore. We've got local maps, but getting lost and exploring is part of the fun.
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Rick Klain
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