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[GS_TECH01]

After checking with our engineers, the ET-332 does support PPS.

[Checho3388]

Hi!, i'm finally working with the ET332 engine board.
I'm trying to get PPS signal but I can't. Is there anything special to do to activate this signal?

Thank you very much!

Ezequiel

[GS_TECH01]

The PPS output is on Pin 11. For more info, please refer to its User Manual on page 6: http://www.usglobalsat.com/store/download/49/et332_ug.pdf

Also, once the engine board acquires a GPS 3D fix, you should be able to see the PPS output.

Let me know how it goes.

[Checho3388]

I'm trying to read the PPS signal via the parallel port of my PC.
I'm running SirfDemo on background to configure the GPS, but i haven't received anything yet.

I don't know if I'm doing anything wrong...
I'd apretiate if you could tell me how to configure my GPS to get that signal.

Thanks!!!

[GS_TECH01]

You can possibly follow the instructions below:

1. Download and install this software: http://www.usglobalsat.com/store/downloads/SiRFDemo387.zip
2. Open up the Sirf Demo software.
3. Connect your device, choose the correct COM port, and select the 4800 baud rate.
4. Go to Action > Open Data Source.
5. You should be able to see some scrolling data in the Debug View window.

Note: Be sure not to click on anything else in this software, as you can render your device unusable.

[Checho3388]

Is this PPS the GPS timemark?... cause i can't see that signal on my scope..

Thanks

[GS_TECH01]

Yes, the PPS is the GPS timemark and it is a very small pulse (1uS) to be measured. So, you need to have a good oscilloscope and equipment in order not to miss the PPS output.

[federoasio]

Hi! I don't have an oscilloscope and I need to know the amplitude of the pps signal. I guess it is 2.85V, but I must be sure so I don't damage the microcontroller I want to use to detect this pulse.

Thanks in advance!

[GS_TECH01]

Hello federoasio,

Welcome to the forums! Our engineers just confirmed that the amplitude of the PPS signal is 2.85V.

Let me know if you have any questions. Thanks.

[federoasio]

Thank you very much! I could detect the PPS signal with an external interrupt in my LPC1769. Weak pull down should be set in the pin used to detect  it (if it helps to someone).
Thanks!

[GS_TECH01]

You're welcome. And, good to hear that you're able to detect the PPS signal.

Also, thanks for sharing your setup procedure. Thanks.