American Megatrends MegaRAC M300V, Руководство пользователя

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40 MegaRAC® M300V Card Implementer’s Reference and User’s Guide
System Control Signals
These signals are used by the MegaRAC M300V card to control some specific, system-level
parameters.
Signal Group: Control
Signal Group Signal Name Signal Function I/O Signal
Termination on
MB*
Control MCARD_CLR_CMOS_L mCard system CMOS clear control O 4.7k PU to +3.3V
MCARD_LOCAL_LOCK_L mCard local lock out control O 4.7k PU to +3.3V
MCARD_SYS_SPKR_DATA mCard system speaker control O N/A
MCARD_SCI_INT_L mCard SCI to the system chipset O 4.7k PU to +3.3V
•
Local access lock out (MCARD_LOCAL_LOCK_L):
•
Assertion of this signal by the MegaRAC M300V card enables a local mode access lock
out mechanism.
•
Clear CMOS control (MCARD_CLR_CMOS_L):
•
The MegaRAC M300V card uses this signal to clear the host system CMOS RAM.
Clearing the CMOS is often necessary after actions such as updating BIOS. Asserting this
signal for at least 250 ms and then deasserting it causes the system CMOS to be cleared.
•
Speaker data (MCARD_SYS_SPKR_L):
•
The BMC may pulse this signal to send tones to the system speaker/transducer that is
typically soldered to the motherboard. This allows the BMC a simple audile alarm
capability. Special motherboard support is required to integrate the BMC speaker control
with that normally provided by the system chipset.
•
System Control Interrupt (MCARD_SCI_INT_L):
•
The MegaRAC M300V card uses this signal to assert an SCI to the system to indicate to
the system that the MegaRAC M300V card has identified an event which requires
attention from the host system. The system will send some system specific IPMI
commands in response to receipt of this signal.