USB GPS interface to FPGA or Microcontroller

[Naumanpak]

Hi experts!

I am doing speed limit indicator and navigation as a semester project using a commercially available GPS.

Got a have Holux m215 USB GPS. I have interfaced it with my laptop in C language, read the USB COM port and implemented the algorithm. It works awesome!

Now I want to implement my system on either FPGA or PIC. But no good knowledge on how to do a USB interface..

How do I
1- read data from from USB receiver into FPGA/PIC?
2- implement the algorithm and display the results on LCD?


many thanks!!

 

[JacquesKleynhans]

Hi Experts please correct me if im wrong in the following.

For the fpga to read and write to a usb device you need a host controller availible, as core i think at opencore.com or you can use an asic device from fdti :vnc1l-1a
.

On the website of fdti there are application notes on pic >> Usb control read and write. The host controller can accept i2c, spi or parallel 8bit data stream in/from.

check out these website they might help you in your quest

http://www.vinculum.com/prd_vnc1l.html
http://www.ftdichip.com/FTProducts.htm

good luck

jacques

 

[mrflibble]

Or alternatively you could use **broken link removed**

It gives you the option of using either usb or a standard serial port. So all you need is two Rx/Tx pins on the fpga and this bit of verilog for the interface.

 

[Naumanpak]

Thanks experts,

What if I use a usb to serial converter?
Will I have to write the drivers for USB?

thanks again

 

[mrflibble]

Hello Naumanpak,

If by that question you mean "If I use connect a usb to serial converter, will I have to bother with USB code?", then no.

Suppose your computer does not have a native serial port, then you can use a usb to serial converter, and on the serial side it will behave like a boring RS232 port. You can just use something like minicom, hyperterminal, your own prog through ttyS0, etc...

But please note I only mentioned the globaltop part as an alternative that does not necessarily need a usb connection. This part gives you the choice to either use USB or use serial (rs232) for communicating with the gps part. I know I like the specs which is why I ordered 2 recently.

If usb is giving you problems (for whatever reason), it might make sense to look for something easier. And since this type of gps application doesn't really need 3452345 mbps bandwidth, why not go for a lowly 9600 baud serial if that makes your design life easier.

If you are still going the USB route and need something to take care of the usb part for you... like JacquesKleynhans said FDTI makes some good usb parts. Also cypress makes a couple of nice micros like the CY7C68013A that takes care of all the usb fun for you.

hope that helps.

 

[Naumanpak]

Ok thanks a lot for help. I will go for this module rather than using my usb receiver.


regards-