Welcome to new LinuxPPS's wiki page!

LinuxPPS provides a programming interface (API) to define in the system several PPS sources.

PPS means “pulse per second” and a PPS source is just a device which provides a high precision signal each second so that an application can use it to adjust system clock time.

A PPS source can be connected to a serial port (usually to the Data Carrier Detect pin) or to a parallel port (ACK-pin) or to a special CPU's GPIOs (this is the common case in embedded systems) but in each case when a new pulse arrives the system must apply to it a timestamp and record it for userland.

Common use is the combination of the NTPD as userland program, with a GPS receiver as PPS source, to obtain a wallclock-time with sub-millisecond synchronisation to UTC.

More detailed information regarding PPS and LinuxPPS are available at Technical information page.

A LinuxPPS's mail list is available at http://www.linuxpps.org/cgi-bin/mailman/listinfo/discussions where you can send to your LinuxPPS related questions (please avoid asking about userland problems nor ntpd or chrony servers, etc.).

Press talked about the LinuxPPS project on:

* Linux&C. issue 68 (year 11) at page 5 (Italian magazine).

* Linux Journal issue 185 (September 2009) at page 14.

* Kenji Hiranuma

* Folkert van Heusden

Other contributions can be done via PayPal.

* LANTIME M200/GPS from Meinberg.

* Many thanks to Meinberg for donating this new WEB space.

* Thanks to Andreas Puls for the LinuxPPS's logo.

* Thanks to World Time Solution for asking to me to do some improvements on LinuxPPS code.