Summary (version 1.0-1)
PKGBUILD and related files form a simple package for enabling the PCF8523 real-time clock on RPi900 boards. A service is provided for automatically synchronising the Raspberry Pi system clock to the real-time clock during system startup.
During package installation your
/boot/config.txt file will be modified to enable the
pcf8523-rtc device-tree overlay. With this modification, the PCF8523 chip will be automatically loaded as
/dev/rtc0 when the Raspberry Pi boots.
The package also installs a systemd service to synchronise the system time from
/dev/rtc0 once it's loaded. (This typically occurs around the 12-second mark.) The service is enabled to run automatically, so no further action is required.
After rebooting, you can observe synchronisation of the clock by typing
systemctl status rpi900-rtc:
* rpi900-rtc.service - RPi900 real-time clock synchronisation Loaded: loaded (/usr/lib/systemd/system/rpi900-rtc.service; enabled; vendor preset: disabled) Active: inactive (dead) since Sun 2015-02-15 14:08:50 AEDT; 2h 29min ago Process: 142 ExecStart=/usr/bin/hwclock --hctosys (code=exited, status=0/SUCCESS) Main PID: 142 (code=exited, status=0/SUCCESS) Jan 01 10:00:13 roof systemd: Starting RPi900 real-time clock synchronisation... Feb 15 14:08:50 roof systemd: Started RPi900 real-time clock synchronisation.
(No reverse synchronisation of the hardware clock from the system clock is performed; the
ntpd time protocol should do this automatically if the Raspberry Pi is network-connected.)
The package installs only a single file:
/usr/lib/systemd/system/rpi900-rtc.service: this systemd service file performs a system clock synchronisation (
hwclock --hctosys) once the hardware clock device becomes available.
- 2015/02/15: version 1.0-1: initial release.