Related to this, I have a GPS receiver generating PPS interrupts on SAME70. It would be a perfect GMC - Atomic clock sync! I will look at this when I get a chance. I have a lot of upstream contributions from HW platforms I have done over the last 5 years or so with myself and others ... I need some time to patch master on upstream -- something for 2023 and now that NuttX has graduated! Yay!
nsh> PPS: sys 227752 slip 0 PPS: sys 243752 slip 17 PPS: sys 259752 slip 0 PPS: sys 275752 slip 10 PPS: sys 291752 slip 8 PPS: sys 307752 slip 0 PPS: sys 323752 slip 4 PPS: sys 339752 slip 0 PPS: sys 355751 slip 0 PPS: sys 371751 slip 22 PPS: sys 387751 slip 0 PPS: sys 403751 slip 0 PPS: sys 419751 slip 4 PPS: sys 435751 slip 0 PPS: sys 451751 slip 9 PPS: sys 467751 slip 0 PPS: sys 483751 slip 0 PPS: sys 499751 slip 0 PPS: sys 515751 slip 12 PPS: sys 499751 slip 0 PPS: sys 499751 slip 0 nsh> PPS: sys 499751 slip 0 On Tue, Dec 6, 2022 at 8:16 PM James Dougherty <jafr...@gmail.com> wrote: > Great project! I've done a few commercial implementation of PHY > timestamping protocols - IEEE1588 for Ethernet 802.3 > and the WLAN version (802.11v2012) for 802.11n. Products with that > technology are still shipping today (but that was 10 years > ago now). Both are key foundations and building blocks for any > time-sensitive networking (in my case RTP streaming Audio and > Video via uni/multicast). You'll find you don't need a heavy weight > implementation for this -on ethernet, it is a mac layer protocol > where all you need to do is tx/rx IEEE ethertype=0x88f7 packets. The SYNC > message is from an 802.1AS grand-master clock. > You will syntonize your local clock from this message and concurrently and > periodically run a PID control loop to adjust your local > phase and epoch over a system-performance specific period. My > recommendation and direction for this development would be to get 2 Linux > boxes with an Intel Ethernet MAC (any intel MAC), read the 1588 spec and > use Wireshark (with linux ptpd and p2p4l as Alan mentioned) > to study the SYNC message exchanges between a GMC and peer (client) > device. Sounds like greek but 1588 is the place to start. > NuttX could fully support this and servo control loop. You can contact me > offline if you need protocol decode or net debug help, I lived > the dream, even have teh T-shirt :) > > Have fun! > > > > > > > On Tue, Dec 6, 2022 at 1:30 PM Alan C. Assis <acas...@gmail.com> wrote: > >> Hi Markus, >> >> I don't know if there is someone already using PTP with NuttX >> (probably since NuttX is used by many industrial automation >> companies). >> >> I think the first step should be add a PTP daemon for NuttX. >> >> The ptpd could be a good candidate: https://github.com/ptpd/ptpd >> >> BR, >> >> Alan >> >> On 12/5/22, Markus Noll <m...@markus-noll.de> wrote: >> > Dear all, >> > >> > I'm just investigating NuttX a bit as there is definitely more and more >> > momentum coming about it. >> > I was just wondering if PTP (IEEE1588) is supported or if this is >> planned >> > for the future? Currently, it doesn't look like this, however some >> Eth-MAC >> > drivers have at least some register-definitions for the >> > timestamping-module. >> > >> > Thanks in advance, >> > Markus >> > >> >
