Raspberry with a gps clock and a etc
RTC
- apt-get install i2c-tools
- cat /etc/modules
pps-gpio <<<< PPS i2c-bcm2708 i2c-dev rtc-ds1307
- modprobe i2c-bcm2708
- modprobe rtc-ds1307
- cat /etc/rc.local
... echo ds1307 0x68 > /sys/class/i2c-adapter/i2c-1/new_device hwclock -s /bin/echo -e '$PMTK314,0,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0*29\r\n' > /dev/ttyAMA0 exit 0
- update-rc.d hwclock.sh enable
- update-rc.d fake-hwclock remove
- apt-get remove fake-hwclock
- rm /etc/cron.hourly/fake-hwclock
- rm /etc/init.d/fake-hwclock
- cat /boot/config.txt
... gpu_mem=16 dtparam=i2c=on dtparam=i2c_arm=on dtoverlay=pps-gpio,gpiopin=23 <<< PPS
- i2cdetect -y 1
- hwclock –systohc -D –noadjfile –utc
NTP
Download: http://www.ntp.org/downloads.html
- apt-get install ntp
- apt-get remove ntp
- cat /etc/udev/rules.d/80-gps-to-ntp.rules
# Change MODE of ttyAMA0 so it is readable by NTP and provide a symlink to # /dev/gps0 KERNEL=="ttyAMA0", SUBSYSTEM=="tty", DRIVER=="", SYMLINK+''"gps0", MODE''"0666" # Symlink /dev/pps0 to /dev/gpspps0 KERNEL=="pps0", SUBSYSTEM=="pps", DRIVER=="", SYMLINK+''"gpspps0", MODE''"0666"
- apt-get install libcap-dev pps-tools
- compile ntpd
./configure --prefix=/usr --enable-all-clocks --enable-parse-clocks --enable-SHM --enable-debugging --sysconfdir=/var/lib/ntp --with-sntp=no --with-lineeditlibs=edit --without-ntpsnmpd --disable-local-libopts --disable-dependency-tracking (--enable-linuxcaps) make make install
alternativ mal probieren NtpBuildOptions
./configure --disable-all-clocks --disable-parse-clocks --without-lineeditlibs --enable-NMEA --enable-LOCAL-CLOCK --enable-SHM --enable-linuxcaps --enable-ATOM
- change /etc/init.d/ntp
sed -i 's/DAEMON=' /etc/init.d/ntp
- hwclock -r
- ntpq -p
- vim /boot/cmdline.txt
- vim /boot/cmdline.txt
- cd /etc/
- * grep ttyAMA0 grep -q ttyAMA0 grep -binr ttyAMA0 * vim securetty grep -binr ttyAMA0 **
- apt-get remove ntp
- cat /etc/udev/rules.d/80-gps-to-ntp.rules
- cat - > /etc/udev/rules.d/80-gps-to-ntp.rules
- apt-get install libcap-dev pps-tools
- find / -name ntpd
- systemctl enable ntp.service
- systemctl status ntp.service
- ntpdate 134.34.3.18
- systemctl start ntp.service
- systemctl status ntp.service
- journalctl -xn
- aptitude purge ntp
- ls -al /etc/init.d/ntp
- /etc/init.d/ntp start
- journalctl -xn
- groupadd -g 123 ntp
- useradd -d /home/ntp -s /bin/false -u 123 -g 123 ntp
- chown ntp:ntp /var/lib/ntp
- mkdir -p /var/log/ntpstats/
- chown ntp:root /var/log/ntpstats/
- systemctl start ntp.service
- systemctl enable ntp.service
- vim /etc/dhcp/dhclient.conf # remove ntp-stuff
ppstest /dev/pps0
- systemctl disable getty@ttyAMA0
- systemctl stop getty@ttyAMA0
- /etc/init.d/ntp start
- systemctl stop serial-getty@ttyAMA0.service
- systemctl disable serial-getty@ttyAMA0.service
- systemctl mask serial-getty@ttyAMA0.service
- cat /etc/ntp.conf
# enable clibrate and make a average of the drift
tail -20 /var/log/ntpstats/peerstats | grep 127.127.22.0 | awk '{SUM=SUM+$5; COUNT=COUNT+1;} END {print SUM/COUNT}'
#Optimisation
echo "performance" > /sys/devices/system/cpu/cpu0/cpufreq/scaling_governor
setserial /dev/ttyAMA0 low_latency
/boot/cmdline.txt smsc95xx.turbo_mode=N
#Check PPS
lsmod | grep pps
ppstest /dev/pps0
ntpd -g -l /var/log/ntpd.log -p var/run/ntpd.pid -c /etc/ntp.conf
gpis readall
sudo apt-get install minicom
minicom -b 115200 -o -D /dev/ttyAMA0