Help With Earthmate USB to Serial Conversion

rgardjr · 02-02-2004, 09:43 PM

I wanted to adapt my USB Earthmate to a serial version. The USB cable only has 2 wires available to send and receive from the Earthmate. Any ideas which pins on a serial port these would connect to? I can buy the cable from Delorme, but I'd like to make one myself and save the $35.
Thanks

Laidback · 02-03-2004, 03:33 AM

Quote: Originally Posted by rgardjr

I wanted to adapt my USB Earthmate to a serial version. The USB cable only has 2 wires available to send and receive from the Earthmate. Any ideas which pins on a serial port these would connect to? I can buy the cable from Delorme, but I'd like to make one myself and save the $35.
Thanks

It's not that simple and I doubt that the cable from Delorme works the way you think it does!

NJay · 02-03-2004, 08:08 AM

I would agree.

The Earthmate USB device is sending the signals in the format for USB. Its the USB to Serial software running on the PC that converts this to look like a com port receiving data.

I would imagine though that the GPS device inside is a serial one with a serial to USB convertor. It may well be possible to bypass that and hook into the GPS device direct???

rgardjr · 02-03-2004, 09:13 PM

Quote: Originally Posted by Laidback

It's not that simple and I doubt that the cable from Delorme works the way you think it does!

You're right. I've got the pin outs and basically the earthmate does support usb or serial, but making my own cable isn't a matter of taking the 2 usb wires and connecting them to a serial plug like I was hoping. I'll buy the Delorme cable and hopefully all my hibernation problems will be solved.