David, > Fine, Folkert. The GPIO pins are numbered in your program exactly > as I would expect, and the diagram just confirms that. Yes, the > patched kernel can remain, and PPS operation should be unaffected. > I was able to drive the two pins (GPIO 18 and GPIO 8) in parallel, > and I have a signal level of about 2.5 V from a resistive divider. > I'm actually driving it from a Trimble SMT module where the serial > is over the USB, and gpsd see the GPS data perfectly.
Ah! Is the serial over usb working stable on your rpi? I have lots of problems with usb devices dropping from the usb bus. Also with a powered hub. > Thanks for the monitoring output. The tie delay between the PPS > leading edge and the change of the monitoring line varies between > 270 to 390 microseconds, so despite the jitter being reported in the > 3-5 microsecond range, the "internal clock" is perhaps running about > 1/3 millisecond behind "real" time. You will be able to see the > performance compared to kernel-PPS here: > > http://www.satsignal.eu/mrtg/performance_raspi-2.php cool! > and a comparison with other stratum-1 Raspberry Pi cards here: > > http://www.satsignal.eu/mrtg/performance_ntp.php > > The software compiled and installed without any issues. I've yet to > figure out how to get it to auto-start - you might like to add that > to your instructions. I may add a section to my Web page with a > step-by-step guide, as this is so much easier than have to use a > non-standard kernel. Will do. For now: edit /etc/rc.local and add the following (BEFORE the exit 0 statement and AFTER the #!/bin/sh line): /usr/local/rpi_gpio_ntp -N 1 -g 8 (replace '8' by the gpio pin) Folkert van Heusden -- Curious about the inner workings of your car? Then check O2OO: it'll tell you all that there is to know about your car's engine! http://www.vanheusden.com/O2OO/ ---------------------------------------------------------------------- Phone: +31-6-41278122, PGP-key: 1F28D8AE, www.vanheusden.com _______________________________________________ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.