HP Book 900 manual System Resources, System Interrupts, System Memory

System Resources

The tables in this section show typical resource usage as set up by the OmniBook BIOS. Plug-and- play operating systems, drivers, and BIOS Setup settings may change some of the entries.

To see other, non-default possibilities, use the BIOS Setup utility (see page 3-24), which lists port and audio device configurations in the System Devices menu.

	Table 1-7. System Interrupts
0	System timer
1	Keyboard
2	Cascade IRQ 9
3	Free (or COM2 infrared port, if enabled)
4	COM1 (serial port)
5	Audio
6	Floppy drive
7	LPT1 (ECP parallel port)
8	Real-time clock
9	Free (OmniBook 900B)
	Video (OmniBook 900†)
10	USB and CardBus - assigned by Windows driver
	Video Controller (OmniBook 900B)
11	Free
12	Pointing device
13	Numeric data processor
14	Internal hard disk (primary IDE controller)
15	Internal CD-ROM drive (secondary IDE controller)

†Models called 900† in this manual have no marking in the serial number, whereas models called 900B have 900 B after the serial number.

	Table 1-8. System Memory
00000 - 9FFFF	System memory
A0000 - BFFFF	Video
C0000 - CBFFF	Video BIOS (OmniBook 900†)
C0000 - CFFFF	Video BIOS (OmniBook 900B)
CC000 - DBFFF*	Free** (OmniBook 900†)
D0000 - DBFFF*	Free** (OmniBook 900B)
DC000*- FFFFF	System BIOS

*Approximate boundary.

**Valid uses for memory addresses CC000-DBFFF or D0000-DBFFF: Upper memory blocks (UMBs).

PC card memory windows.

†Models called 900† in this manual have no marking in the serial number, whereas models called 900B have 900 B after the serial number.

HP OmniBook 900 Product Information 1-7