@rush-2112 wrote:

Thats kinda close… but I need to do it on the real cheap…AKA FREE. so I guess i am loking for the wire schematic for the garmin gpsIII data cable and the proper wireing to convert it to usb. I hope it makes sense.

It makes sense, but it is not possible. While USB stands for universal serial bus, its operation is nothing like the “old” (RS232) serial port standard. Different voltages, different signaling methods, the fact that USB supports multiple end nodes, etc. means that you just cannot solder wires from a USB connector to a serial cable and have it work.

Even the home brew USB to serial design/schematic that Averith dug up uses a USB to serial chip (FT232). My guess is that you’d pay more to buy a single quantity of this chip than it would cost to buy an actual USB to serial port converter…

I recently purchased such a cable. I shopped around for the best price. Best Buy and Curcuit City were very expensive. Office Depot was up there. Super Wal-mart came thru for me much cheaper.

Hint, I learned this one the hard way a year ago .. you will need to install drivers to make it work .. and be sure to install the drivers on any computer you plan to use the cable with.