Ide Controller; Keyboard And Mouse - Silicon Graphics 1450 User Manual

2: Baseboard Description

IDE Controller

Keyboard and Mouse

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IDE is a 16-bit interface for intelligent disk drives with AT disk controller electronics
onboard. The Open South Bridge (OSB4) acts as a PCI-based fast IDE controller. The
device controls:
• PIO and IDE DMA/bus master operations
• Mode 4 timings
• Transfer rates up to 33 MBbs.
• Ultra DMA 33 capacity
• Buffering for PCI/IDE burst transfers
• Master/slave IDE mode
• Up to two drives for one IDE channel
Note: An IDE signal cable can be connected up to the IDE connector on the baseboard.
However, the maximum length of the cable is 18 inches. The cable supports up to two
devices, one at the end of the cable and the other six inches from the end.
The PS/2-compatible keyboard and mouse connectors are mounted in a single-stacked
housing with the mouse connector over the keyboard. Externally, they appear as two
connectors.
The user can plug in the keyboard and mouse to either connector before powering up the
system. The BIOS detects these and configures the keyboard controller accordingly.
The keyboard controller is functionally compatible with the Intel 8042A micro controller.
The system can be locked automatically if no keyboard or mouse activity occurs for a
predefined length of time, if specified through the SSU. Once the inactivity (lockout)
timer has expired, the keyboard and mouse do not respond until the previously stored
password is entered.
007-4274-001