From d50056c252de758c21e28606056de58d64b55950 Mon Sep 17 00:00:00 2001 From: Steven Baltakatei Sandoval Date: Tue, 13 Oct 2020 18:37:15 +0000 Subject: [PATCH] doc(time):Prpeare update for README --- doc/time/README.org | 36 ++++++++++++++++++++++++++++++------ 1 file changed, 30 insertions(+), 6 deletions(-) diff --git a/doc/time/README.org b/doc/time/README.org index 6ec544d..593b411 100644 --- a/doc/time/README.org +++ b/doc/time/README.org @@ -1,7 +1,8 @@ -* Time +* Time Tracking This document was created by Steven Baltakatei Sandoval on ~2020-07-23T22:27Z~ under a [[https://creativecommons.org/licenses/by-sa/4.0/][Creative Commons BY-SA 4.0 license]]. It -was updated by Steven Baltakatei Sandoval on ~2020-10-12T22:22Z~ +was updated by Steven Baltakatei Sandoval on ~2020-10-13T18:02Z~ + ** Development Task list *** Set up prototype unit **** DONE Solder wire for PPS signal @@ -13,6 +14,21 @@ was updated by Steven Baltakatei Sandoval on ~2020-10-12T22:22Z~ - [[https://gpsd.gitlab.io/gpsd/gpsd-time-service-howto.html][GPSD dev ref]] page for ~gpsd~ interfacing with ~ntp~. - [[https://raspberryautomation.com/connect-multiple-ds18b20-temperature-sensors-to-a-raspberry-pi/][Raspberry Autom]] article on specifying custom GPIO pin. *** Document prototype unit +**** Summarize setup steps +***** Perform main setup steps +***** Install time-specific apps +: $ sudo apt install usbmount eject gpsd gpsd-clients python-gps pps-tools ntp + +Explanation: + +- ~python-gps~: (Add explanation here) +- ~pps-tools~: Package containing ~ppstest~ command useful for + checking status of PPS devices. +- ~ntpsec~: Security-hardened version of ~ntp~, the Network Time + Protocol package. Useful for automatically setting the system clock + according to time servers or local hardware. + + **** TODO Integrate DHCP details from gregledet tutorial http://www.gregledet.net/computers/building-a-stratum-1-ntp-server-with-a-raspberry-pi-4-and-adafruit-ultimate-gps-hat/ **** TODO Note working ntp.conf file @@ -108,14 +124,20 @@ restrict source notrap nomodify noquery ** Narrative The ~ninfacyzga-01~ device is equipped with an Ozzmaker BerryGPS-IMU -module which provides time and location data to ~gpsd~. The time is -provided by GPS satellites which themselves are [[https://science.nasa.gov/science-news/science-at-nasa/2002/08apr_atomicclock/][equipped]] with atomic -clocks. This extremely accurate set of clocks are needed since a GPS -receiver calculates its position in space using a General Relativity +module which provides time and location data to ~gpsd~ and ~ntp~. The +time is provided by GPS satellites which themselves are +equipped [fn:nasa_20020408_atomicclock] with atomic clocks. This +extremely accurate set of clocks are needed since a GPS receiver +calculates its position in space using a General Relativity calculation that uses the small variations in the time stamps received from each satellite. This means that ~gpsd~ may be used to set the system clock without a need for an internet connection to a default Debian time server; ~ninfacyzga-01~ can be its own time server. + +[fn:nasa_20020408_atomicclock] Title:[[https://science.nasa.gov/science-news/science-at-nasa/2002/08apr_atomicclock/][Tick-Tock Atomic Clock]]; +Date:2002-04-08; Website:NASA.gov; [[https://web.archive.org/web/20100429141752/http://science.nasa.gov/science-news/science-at-nasa/2002/08apr_atomicclock/][Archive-link]]; Archive-date: +2010-04-29 + ** Description *** Hardware Ozzmaker BerryGPS-IMU, Version 3 @@ -125,6 +147,8 @@ into a time server using ~gpsd~. ** Operating Procedures *** Initial Startup **** Install Raspbian 10 (Buster) onto a Raspberry Pi Zero W. + + **** Install Hardware See [[https://ozzmaker.com/forums/topic/connecting-gps-pps-pin/][this]] Ozzmaker forum topic about connecting the BerryGPS-IMU ~T_PULSE~ pin to GPIO 18. -- 2.30.2