GPS acting up?

Tymkrs

Hi folks,

I've got a GPS Internal Antenna here and I've never had any issues with it before. Now I've got it hooked as I'd expect to - VSS/VDD/Pin 7 on my PropBoe and when I run some code I've had working before, all I get is

---,---,0,0,---,-1,-1,-1,-1,-1,-1

And when I run a demo code, I still only get dashes.

Any ideas?

SRLM

Can you hook it up to a Prop plug, and use it with a terminal to see exactly what the output is?

Tymkrs

So I hooked up the TTL Tx line (yellow) to the Rx on the prop plug, and black to ground, red to 5v...is that right?

SRLM

Rx and Tx are usually relative to the device. So, you would want to hook the GPS Tx line to the PropPlug Rx line. Also, you need the GPS power connection and a common ground.

Tymkrs

So I hooked the GPS Tx Line (PMB-648) to the Prop Plug Rx line, GPS power to the 5V on the Prop Boe, and GPS GND to Prop Boe's GND. I then connected the ground of the propboe to the ground of the prop plug.

GPS was a steady red (no blinking to indicate it needed to find satellites). And I set the baud rate on the Parallax Serial Terminal to 4800. Checked all comports that it found active = nothing.

Tymkrs

Then took a scope to the lines and found in order of Pins 1-6

~1.2v - slightly wavey line, +5v, VCC, GND, -5v - super damped sawtooth looking wave, nothing

Tymkrs

Well. I have no idea, so I guess I'll have to bring it to the Parallax Expo - see if any of you guys can figure it out when we're all together