82091AA Datasheet, PDF (202/204 Pages) Intel Corporation – ADVANCED INTEGRATED PERIPHERAL (AIP)

82091AA
Figure 100 Enhanced Tape Drive Register
290486 – A3
Bit
Description
7 3 Reserved
2 Boot Drive Select (BOOTSEL) The BOOTSEL bit is used to remap the drive selects and motor
enables The functionality is shown below
BOOTSEL
0
1
Mapping
x x DS0 FDS0 ME0 FDME0 (default)
DS1xDS1 x ME1 FDME1
DS0xDS1 x ME0 FDME1
DS1xFDS0 x ME1 FDME0
Only drive 0 or drive 1 can be selected as the boot drive
1 0 Tape Select (TAPESEL 1 0 ) These two bits are used by software to assign a logical drive number
to be a tape drive Other than adjusting precompensation delays for tape support these two bits do
not affect the FDC hardware They can be written and read by software as an indication of the tape
drive assignment Drive 0 is not available as a tape drive and is reserved as the floppy disk boot
drive The tape drive assignments are as follows
Bits 1 0
00
01
10
11
Drive Selected
None (all are floppy disk drives)
1
2
3
A-6