Getting Started
Page 29
Enabling the watchdog (if it's not enabled inside the BIOS firmware):
Triggering the watchdog:.
2.7.2
Managing RTC Time Adjustments
During the boot process, the CPU firmware gets the time from the system RTC (ERTC)
and sets the CRTC accordingly. In the next step, the operating system (OS) gets the time
from the CRTC and sets the system time accordingly. Now the OS system time is updated
independently of the CRTC via periodic clock interrupts. Thus, over time (i.e. as the
system runs), the system time may become out of sync with the CRTC/ERTC time.
If the system time is adjusted (e.g. by the user), the CRTC time will not be automatically
adjusted by the time management, because the OS is not aware of the additional ERTC.
The ERTC time will not be updated and is out of date. During the next system boot, the
OS would use the outdated time.
MEN provides a dedicated ERTC driver to manage system time adjustments.
$
sudo i2cset -y 9 0x4d 0x11 0x00
$
sudo i2cset -y 9 0x4d 0x13 0x00
Chapter 5.3 BMC API (Application Programming Interface) on page 56
for a
detailed description of the BMC API.
See the MEN website for the
Application Note "Using the System RTC
(ERTC) on MEN CPUs under Linux"
.
