HP OmniBook 7100 Reference Manual page 132

Specifications and Regulatory Information
Valid uses for memory addresses D0000-DBFFF:
Upper memory blocks (UMBs).
PC Card memory windows.
170-177 Secondary HDD controller (internal CD-ROM)
1F0-1F7 Internal hard disk
220-22F Crystal sound
376 Secondary HDD controller (internal CD-ROM)
378-37F LPT1 (printer port)
388-38B Sound
3B0-3BB VGA adapter
3C0-3DF VGA adapter
3E0-3E1 PCMCIA controller
3F0-3F5 Floppy controller
3F6 Primary HDD controller
3F7 Floppy controller
3F8-3FF COM1 (serial port)
0 Sound record
1 Sound playback
2 Floppy drive
3 LPT1 (ECP parallel port)
4 Cascade
5 Free
6 Free
7 Free
8-6