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start [2018/08/23 18:40]
giometti created
start [2020/11/26 16:06]
giometti [LinuxPPS based projects] New project added
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 Welcome to new LinuxPPS'​s wiki page! Welcome to new LinuxPPS'​s wiki page!
  
-//This is temporary placeholder.//+===== Overview ===== 
 + 
 +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. 
 + 
 +===== Resources ===== 
 + 
 +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.). 
 + 
 +However **before** sending your questions to this list, please, **take ​look** to the [[LinuxPPS FAQ]] page! 
 + 
 +===== LinuxPPS based projects ===== 
 + 
 +Projects using LinuxPPS: 
 + 
 +  * Dedicated Short Range Communications (DSRC) radio synchronization used by US-DOT'​s VII [[http://​www.its.dot.gov/vii/]] [[http://​en.wikipedia.org/​wiki/​Vehicle_infrastructure_integration]]. 
 + 
 +  * [[http://​www.mmarray.org/​|Owens Valley Radio Observatory]] (OVRO / CARMA) correlator system. 
 + 
 +  * [[http://​ntpi.openchaos.org/​pps_pi/​|Raspberry Pi Stratum 1 NTP server with PPS]]. Accurate timekeeping at low cost. 
 + 
 +  * [[https://​github.com/​rascol/​PPS-Client|PPS-Client daemon for Raspberry Pi 2, 3 or 4 B or B+ or an AMD/Intel desktop system]]. Accurate time keeping precision of a timeline with a standard deviation of 0.5 microsecond and a typical time keeping accuracy of 2 microseconds. 
 + 
 +If you have a project that is using LinuxPPS and you would like it to be shown here, please email [[giometti@ennenne.com]]. 
 + 
 +===== Press ===== 
 + 
 +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.  
 + 
 +===== Contributors ===== 
 + 
 +==== PayPal ==== 
 + 
 +  * Kenji Hiranuma 
 + 
 +  * [[http://​www.vanheusden.com/​|Folkert van Heusden]] 
 + 
 +Other contributions can be done via [[http://​paypal.me/​RodolfoGiometti|PayPal]]. 
 + 
 +==== Hardware ==== 
 + 
 +  * [[http://​www.meinberg.de/​english/​products/​lantime-m200-gps.htm|LANTIME M200/GPS]] from [[http://​www.meinberg.de/​Meinberg | Meinberg]]. 
 + 
 +==== Misc ==== 
 + 
 +[[https://​www.meinbergglobal.com/​|{{:​meinberg_logo.png?​nolink&​100 | Meinberg}}]] 
 + 
 +  * Many thanks to [[https://​www.meinbergglobal.com/​|Meinberg]] for donating this new WEB space. 
 + 
 +  * Thanks to [[andreas.puls@meinberg.de|Andreas Puls]] for the LinuxPPS'​s logo. 
 + 
 +  * Thanks to [[http://​www.worldtimesolutions.com/​|World Time Solution]] for asking to me to do some improvements on LinuxPPS code. 
 + 
 +     
start.txt · Last modified: 2020/11/26 16:06 by giometti