Hello!
Long time FreeBSD user here, first started with v5.0 and a software and electronics engineer - just for some background.
In the past I've previously used a WRAP board with an Oxford chipset-based RS-232 to provide real hardware-based RS-232 (with a few kernel source changes so it is recognised) to provide NTPD with an GPS-based timesource which also provided PPS via the DCD pin. That setup worked great and I built it with NanoBSD scripts.
Now, moving on at least a decade, things have of course moved on...
I was looking at repurposing my APU2 device as it was expensive (at the time) and I thought that I should bring back my own time server.
I had a Garmin GPS 18 which was wired during the WRAP days and I soldered up the connector to provide both PPS and NMEA. But I noticed (recently-ish) that PPS via either DCD or CTS pin via USB was now actually supported - https://lists.freebsd.org/pipermail/freebsd-usb/2019-August/016078.html
But upon my own research and testing, that doesn't actually seem to true. I even e-mailed the OP of that thread asking for more information but that e-mail bounced back. I've tried to feed in a PPS signal via both DCD and CTS and every app (GPSD, NTPD, and Chrony) via USB and it just ignores it. Tried numerous USB adapters which even provided those pins but it seems that either the app or FreeBSD just ignores PPS by USB-based devices. It ONLY seems to work if it's a REAL hardware-based RS-232 port (ie UART). So why does "Ian" claim that it worked for him?
Can someone help shed some light on this? As that list thread seemed to claim that everything was working but it seems that it isn't. Or did I miss something very obvious?
Additional information available on request.
Thanks in-advance,
Danny.
Long time FreeBSD user here, first started with v5.0 and a software and electronics engineer - just for some background.
In the past I've previously used a WRAP board with an Oxford chipset-based RS-232 to provide real hardware-based RS-232 (with a few kernel source changes so it is recognised) to provide NTPD with an GPS-based timesource which also provided PPS via the DCD pin. That setup worked great and I built it with NanoBSD scripts.
Now, moving on at least a decade, things have of course moved on...
I was looking at repurposing my APU2 device as it was expensive (at the time) and I thought that I should bring back my own time server.
I had a Garmin GPS 18 which was wired during the WRAP days and I soldered up the connector to provide both PPS and NMEA. But I noticed (recently-ish) that PPS via either DCD or CTS pin via USB was now actually supported - https://lists.freebsd.org/pipermail/freebsd-usb/2019-August/016078.html
But upon my own research and testing, that doesn't actually seem to true. I even e-mailed the OP of that thread asking for more information but that e-mail bounced back. I've tried to feed in a PPS signal via both DCD and CTS and every app (GPSD, NTPD, and Chrony) via USB and it just ignores it. Tried numerous USB adapters which even provided those pins but it seems that either the app or FreeBSD just ignores PPS by USB-based devices. It ONLY seems to work if it's a REAL hardware-based RS-232 port (ie UART). So why does "Ian" claim that it worked for him?
Can someone help shed some light on this? As that list thread seemed to claim that everything was working but it seems that it isn't. Or did I miss something very obvious?
Additional information available on request.
Thanks in-advance,
Danny.