HP OmniBook 4150 Reference Manual page 131

DMA Channels
0 Sound Record (unmarked models*)
Free ("4150 B" models*)
1 Sound playback
2 Floppy drive
3 LPT1 (ECP parallel port)
4 Cascade
5 Free
6 Free
7 Free
* Unmarked models have no "4150" after the serial number, "4150 B" models have
"4150 B" after the serial number.
Specifications and Regulatory Information
Software System Resources
Reference Guide 131