Connected this module to the MBED :

http://www.f-tech.com.tw/modules/publisher/item.php?itemid=5

4 pins -> Ground, VOUT, & pins 27,28.

is it possible there is insufficient 3.3v to power this GPS ?

the code I am playing with:

1. include "mbed.h"

Serial pc(USBTX, USBRX); tx, rx

Serial device(p28, p27); tx, rx

int main() {

pc.baud(115200);

device.baud(38400);

pc.printf("starting\r\n"); (does print on my putty)

device.printf("$PMTK220,250*29\r\n");

device.printf("$PMTK103*30\r\n");

device.printf("$PMTK251,38400*27\r\n");

while(1) {

if(pc.readable()) {

device.putc(pc.getc());

}

if(device.readable()) {

pc.putc(device.getc());

}

}

}

problem solved.... Board is too noisy for GPS... Need to shut down Ethernet MAC and lower CPU speed to 48Mhz.

increase separation?

I am not 100% sure it is 'radiating'... it might come down the hard lines. Need to put the setup next to a spectrum analyzer...

Good to see someone found a solution to this problem. It seems to be radiating. I powered them with two isolated supplies (no RS232 link) and as soon as I get the mbed close to the GPS (1-2" away) it looses its satellite signal.