Using Power Save Mode on U-Blox GPS receiver (SODAQ One)

Hi,
I’m trying to build my own tracking deveice using the SODAQ One. In order to save energy, I wanted to make use of the Power Save Mode implemented in the U-Blox GPS receiver. After studying their datasheet for a while, I came across the following methods to wake up the receiver from it’s sleep:

The receiver can be woken up by generating an edge on one of the following pins:
• rising or falling edge on one of the EXTINT pins
• rising or falling edge on the RXD1 pin
• rising edge on NRESET pin

Now from my understanding of reading the SODAQ One schematics, none of these pins are connected on the board. So I came to the conclusion that it’s impossible to use the Power Save Mode.
Am I correct with this assumption or is there something I missed?
Any help would be greatly appreciated

The primary power supply to the GPS is switched on and off with GPS_ENABLE. A secondary backup source VCC_BCKP should keep certain components running but in low power mode.

I’m not sure the differences between that low power mode and the one you are referring to.

Yeah I got that. But if I’m using the Power Save Mode provided by U-Blox (as per their datasheet), I need to be able to wake it up again with either the EXTINT, RXD1 or NRESET pin of the GPS receiver. My question is simply if these pins are actually connected on your board or not, because it looks like they aren’t according to your schematics.

I don’t believe any of those pins are connected (as per the schematic). You will have to mod your board to attach one of those pins to an IO pin.

I would suggest you argue the benefits of using that specific mode you mention. There is a good chance that the required modification could be included in the next hardware revision.

Hello!

First at all, I apologize for making noise on this old thread. But it is indeed the one that best suit to my question.

I would love to know what HW version of the board they were referring at that time (January 2017). And more important, if there is any way to put the Sodaq ONE v3 to sleep while keeping the U-Blox GPS acquiring satellite signals., in order to save energy.

Thank you in advance!

Hi @barillaro,

Yes, you can have the microcontroller sleeping and the gps active.

It’s like Gabriel mentioned here:

digitalWrite(GPS_ENABLE, TRUE); to power on the GPS, this doesn’t have any effect when the microcontroller goes to sleep, if you want to turn off the GPS you can set FALSE.

When you obtain a fix, turn off the GPS, the search for satellites stops but the almanac is stored. When you re-enable the GPS you can do a hot fix and have a fix much faster due to the backup power.

Best regards,
Jan