Hi, Years(?) ago I wrote a program rpi_gpio_ntpd to be able to use a pps with a raspberry pi (or any other linux system with standard gpio pin support) and ntp. Works fine altough the jitter is between 0 and 15us. http://www.vanheusden.com/time/rpi_gpio_ntp/
By accident I read https://github.com/raspberrypi/linux/issues/109 where it is written that the standard(?) image (the one installed with the "rpi_update" script) now includes kernel gpio pps support! I've installed that kernel and indeed, there now is a /sys/module/bcm2708/parameters/pps_gpio_pin "file" to which you "echo" the pin number on which you feed the pps signal. I tested it...and could not get it to work. gpsd opens pps0 but strace does not show me the regular ppsapi syscalls and also ppstest gives a time out. I'm probably missing something trivial here but if any other of you would like to give it a try please let me know (here) if and how you succeeded! Folkert van Heusden -- ---------------------------------------------------------------------- Phone: +31-6-41278122, PGP-key: 1F28D8AE, www.vanheusden.com _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
