AradoSKYindi wrote: Hello,

Under KSTARS and INDI, GPSD is PPS based under Ubuntu. With Raspbian, CHRONY provides time. I would suggest using GPSD and properly configure it. I never thought to use GPS for time. PPS was it.

PPS is a logic-level electrical 1hz signal. Unless you see a separate wire from your dongle attached to one of the GPIO pins on the Raspberry Pi, then no, you don't have PPS active, and no, GPSD isn't using what it doesn't have.

To enable PPS in GPSD, you must first create a /dev/ppsXX device. That is normally done by using a dtoverlay, which requires the explicit naming of the GPIO pin the PPS signal is received on. Don't know whether GPSD can be started with a missing device named in its config file or not.

AradoSKYindi wrote: U-Blox 7 device provides PPS. PPS is part of their setup requirements. Besides, my KSTARS GPS sampling rate is 15 minutes. Within KSTARS, I can update as needed manually. As long as I know where I am, a GPS dongle, (properly configured), is a welcomed addition.

Well, here's the manual and spec sheet for the U-Blox receiver, as published by the manufacturer: UBLOX-7 Manual

You'll note, that the receiver can provide a PPS pin, but only if it's packaged that way. USB is not one of the ways. Nor is PPS any part of it's "setup".

Clearly, your understanding of GPS in general, is insufficient to accurately advise others on the subject.

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