DIGITAL-LOGIC MSM800BEV, Техническое руководство пользователя

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DIGITAL-LOGIC AG
MSM800SEV/SEL/BEV/XEV/XEL Detailed Manual V1.7
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5.6.2. RTC (Real Time Clock)
An AT compatible date/time clock is located within the chipset. The device also contains a CMOS static
RAM, compatible with that in standard ATs. System configuration data is normally stored in the clock chip's
CMOS RAM in a manner consistent with the convention used in other AT compatible computers.
Connect an external Lithium battery to X33 pin6 (or use the mounted battery). Be sure to use the correct
polarity!
The battery-backed clock can be set by using the DIGITAL-LOGIC AG SETUP at boot-time.
Note…
On all MSM800SEL/BEL/XEL boards – the battery must be connected externally! There is no
battery assembled onboard.
Attention!
For systems that already have an onboard battery (MSM800SEV/BEV/XEV): if an external battery
is to be connected, then the onboard battery
must be removed first.
5.6.3. Watchdog
The watchdog timer detects a system crash and performs a hardware reset. After power up, the watchdog is
always disabled as the BIOS does not send strobes to the watchdog. In case the user wants to take
advantage of the watchdog, the application must produce a strobe at least every 800 ms. If no strobe occurs
within the 800 ms, the watchdog resets the system.
For more information, please refer to the driver/software/BIOS manual “GEODE_LX800-LX900” on the
Product CD. The watchdog feature is integrated in the INT15 function.
There are some programming examples available:
Product CD-Rom or customer download area: \tools\SM855\int15dl\…