From: Mark Sims

A couple of people have asked about the poor message arrival time performance of the popular Adafruit Ultimate GPS receiver. I modified Lady Heather to analyze the message arrival times using a histogram instead of a simple average. When I looked at the histogram data (.01 msec resolution), I was rather shocked... With an hour of data, most receivers have maybe a couple dozen bins hit, with the peak bin several hundred counts above the next lower peak. The Adafruit had over 1800 bins hit, with the peak bin having six hits. Attached is the histogram... you probably don't want to use this receiver to drive a clock based upon message arrival times...
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Mark,

Are you sure that the arrival time is negative? In my experience, the NMEA message is /after/ the PPS, and not before it.

Cheers,
David
--
SatSignal Software - Quality software written to your requirements
Web: http://www.satsignal.eu
Email: david-tay...@blueyonder.co.uk
Twitter: @gm8arv
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