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Lora-net / lora_gateway

Driver/HAL to build a gateway using a concentrator board based on Semtech SX1301 multi-channel modem and SX1257/SX1255 RF transceivers.
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XTAL error calc not using NAV-TIMEGPS #168

Closed pshep closed 2 years ago

pshep commented 3 years ago

Should this: https://github.com/Lora-net/lora_gateway/blob/a955619271b5d0a46d32e08150acfbc1eed183b7/libloragw/src/loragw_gps.c#L678 Not use gps_time, not utc for calculating the 'slope'?

On a separate but related topic, I understand the NAV-TIMEGPS is used to avoid leap seconds in the NMEA stream, but why are they an issue? I assume it's got something to do with the possibility of time going backwards?

3rdly... right there we're measuring the time between PPS pulses. Should this not be expected to be exactly 1 second (within 30ns or so)? Why even measure the period over hard-coding to 1 second?

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