NEC READY ES PRO, Service And Reference Manual

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CMOS memory. The chip also contains the system’s real-time clock. Both are maintained by a 3-volt coin cell
lithium battery on the system board. The battery is replaceable.
DMA/
IRQ
Settings
The system automatically configures interrupt requests (IRQ), direct memory access (DMA) channels, and
other parameters when adding PCI boards with minimal user intervention.
Table 1-3 and Table 1-4 list system IRQ and DMA default settings.
* Default, but can be changed.
IDE Ports
Table 1-3 Interrupt Level Assignments
IRQ System Resource
NMI I/O channel check
00 Reserved, internal timer
01 Reserved, keyboard buffer full
02 Reserved, cascade interrupt form slave PIC
03 COM2*
04 COM1*
05 LPT2 (Plug and Play option)/Audio/User available
06 Diskette drive
07 LPT1*
08 Real-time clock
09 User available
10 User available/USB
11 Windows Sound System*/User available
12 Onboard mouse port (if present, else user available)
13 Reserved, math coprocessor
14 Primary IDE (if present, else user available)
15 Secondary IDE (if present, else user available)
Table 1-4 DMA Assignments
DMA Resource
00 Audio
01 Audio/Parallel port
02 Diskette drive
03 ECP parallel port/Audio
04 Reserved, cascade channel
05 Available
06 Available
07 Available