GPIO PPS Client

In this example I've choose pin #7 to be my PPS input. You can use any other GPIO Here.

Enabling GPIO PPS Client

sudo -s
apt-get install device-tree-compiler pps-tools
fdtput -c /media/boot/meson8b_odroidc.dtb /pps
fdtput -t s /media/boot/meson8b_odroidc.dtb /pps compatible "pps-gpio"
fdtput -t s /media/boot/meson8b_odroidc.dtb /pps gpios "GPIOY_3"

Reboot the board to test.

Testing GPIO PPS Client

Start feeding the signal to the selected pin (#7 in this example). Remember that the logic voltage is 3.3V.

sudo -s
ppstest /dev/pps0

Will output something like:

source 0 - assert 1439248167.494093618, sequence: 552 - clear  0.000000000, sequence: 0
source 0 - assert 1439248167.494140618, sequence: 553 - clear  0.000000000, sequence: 0

Note this example will only run on kernel 3.10.80-122 or greater.