SparkFun Forums 

Where electronics enthusiasts find answers.

Tips and questions relating to the GPS modules from SFE
By Oznog
#45536
I was thinking about trying one of these out, saw them on eBay like this one with the MTK MT3318 chipset, but they talk about Bluetooth interface which isn't gonna work with a microcontroller, not without more additional complexity than I want to get into. In fact the world looks to be awash in cheap 32 ch bluetooth devices.

Now I did see this:
Output terminal: Mini-USB (CMOS Level):
NMEA protocol output : V 3.01
Baud Rate: 38400 bps
Data bit: 8
Parity: N
Stop bit: 1

but I'm also seeing something called Bluetooth Serial Port Profile (SPP) and it looks like this may mean this is a 38400 8N1 serial link implemented on a Bluetooth wireless link, which I still won't be able to use. Am I right about this being a wireless protocol or did I miss something?

Is there a physical serial link between an internal GPS module and the bluetooth motherboard that could be physically hacked for microcontroller interfacing via standard UART?

Hmm, I found the manuals and it does look like the baud rate pertains to a virtual com port set up through bluetooth. However, I also see that it says a "normal" USB cable won't work for the USB connection, something called a "gMouse" cable they sell special. I'm getting the impression that this device does use RS232, and this cable's hardware box (there's clearly some hardware in the middle of the cable) is an RS232-to-USB bridge. Anybody able to confirm or deny this theory?
By velocet
#45548
Just took a quick look, the device is dual function. Bluetooth and serial. The SPP relates to the bluetooth part which you can pretty much use with any BT laptop/PDA or phone.

The Micro USB is supplying serial at cmos level so you with have convert to what ever interface you require after you have figured out the pinout.