Power Management; I/O Addressing - NEC POWERMATE P - SERVICE MANUAL 1996 Service And Reference Manual

Memory Space
00080000-0009FFFF
00000000-0007FFFF

Power Management

Each system incorporates power management features that lower power consumption when
there is no activity detected from the keyboard, mouse, diskette drive, CD-ROM reader, or
hard disk drive after a pre-defined period of time. As soon as activity is detected the system
resumes where it left off.
With Power Management enabled (shipped enabled), the system automatically activates the
power-saving features and enters a suspend mode whenever inactivity is sensed. The
system's power-saving functions are as follows.
n
Reduces CPU clock speed
The CPU, cache, and video clock speeds are reduced, putting the system in the
suspend mode.
n
Blanks out the monitor
Puts the video controller into suspend mode. The vertical sync clock and blank
signals to the monitor are disabled.
n
Forces the IDE devices into stand-by mode
A suspend command is sent to the IDE devices which put the devices into a
stand-by mode.

I/O Addressing

The processor communicates with I/O devices by I/O mapping. The hexadecimal (hex)
addresses of I/O devices are listed in Table 1-3.
Table 1-2 System Memory Map
Size To
128 KB 640 KB
512 KB 512 KB
Technical Information
Function
Optional memory space gap (DOS
applications)
DOS applications (no read/write protect;
always cacheable)
1-7