DIGITAL INPUT REGISTER (DIR)
Address 3F7 READ ONLY
This register is read-only in all modes.
PC-AT Mode
7
6
5
4
3
2
1
0
DSK
CHG
RESET N/A N/A N/A N/A N/A N/A N/A N/A
COND.
BIT 0 - 6 UNDEFINED
The data bus outputs D0 - 6 will remain in a
high impedance state during a read of this
register.
BIT 7 DSKCHG
This bit monitors the pin of the same name and
reflects the opposite value seen on the disk
cable or the value programmed in the Force
Disk Change Register (see Configuration
Register LD8:CRC1[1:0]).
30