Yes, it’s good stuff. I will look at it next year.
> On Dec 7, 2022, at 5:41 PM, Nathan Hartman <hartman.nat...@gmail.com> wrote: > > On Tue, Dec 6, 2022 at 11:16 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 :) > > > > If this support could be built into NuttX that would be awesome. Some of my > products are built on the TI Tiva-C series which includes hardware 1588 > support in the on-chip Ethernet MAC (or PHY, I don't remember which--the > chip has both) and I have wanted to use 1588 but could never figure out how > to make it work. It has been probably 4 or 5 years since I last looked into > it, though. > > Cheers > Nathan
