duagon MC50M, User Manual, Page: 45 / 85

Getting Started
20MC50M00 E5
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2020-10-20 45
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 (Chipset Real-Time Clock) 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The ERTC time will not be updated and is out of date.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OS would use the outdated time.
duagon provides a dedicated ERTC driver to manage system time adjustments.
2.7.3 Configuring the Serial Interfaces
The ASIX AX99100 UART controller is installed automatically.
See the duagon website for user manual Windows ERTC/SMB Support
Package .
In a modular DIN-rail system, the ASIX driver handles all of the serial
interfaces of the system. You have to install the driver once on the MC
module (CPU) and can configure all of your serial interfaces on system
level, including those on ME modules.