MEN BL70S, Руководство пользователя

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Getting Started
20BL70S00 E3

2018-06-11 Page 38
2.8.4 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 ERTC 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The ERTC time will not be updated and is out of date.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OS would use the outdated time.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.
2.8.5 Setting the UART Modes of BL70S Interfaces
MEN provides a Linux tool that allows to switch the UART modes of legacy serial I/O
interfaces.
The Linux tool supports the following BL70S interfaces (front panel designations):

X1

X2
See the MEN website for application note Using the System RTC (ERTC) on
MEN CPUs under Linux .
See the MEN website for more information and documentation:
www.men.de/software/13sc24-91/