Re: [L4s-discuss] [EXTERNAL] rpi 5 and hardware ptp

rjmcmahon <rjmcmahon@rjmcmahon.com> Mon, 08 April 2024 18:08 UTC

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Date: Mon, 08 Apr 2024 11:08:48 -0700
From: rjmcmahon <rjmcmahon@rjmcmahon.com>
To: "Overcash, Michael (CCI-Atlanta)" <michael.overcash=40cox.com@dmarc.ietf.org>
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Subject: Re: [L4s-discuss] [EXTERNAL] rpi 5 and hardware ptp
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> What about iPhone / Android ecosystems ... is anything possible there?
> Those devices all have integrated GPS already, although I don't know
> if an app could practically utilize it.
> 
I don't know of a way to get either PPS or PTP hardware timestamps on 
those platforms. They do have their own GPS chips and tend to have 
temperature compensated oscillators (TCXO) but not sure how well the 
system clock is synced to the GPS atomic clock. We tend to use reference 
hardware in our rigs for these and not actual devices. The iOS devices 
are even more challenging for many non technical reasons.

It would be great if there was a way to address these platforms to have 
the system clocks always synced to the GPS atomic.

Bob