Philips CD-I - Page 89

1.2. Floppy disk drives and interface
1.2.1 Floppy Disk Interface
The floppy disk interface supports two floppy disk
drives using DMA transfer.
- Address 330000 - 33FFFF
- Access Byte access only (odd addresses).
- Internal registers
Address
330001
330003
330005
330007
Read
status register
track register
sector register
data register
- Support register
Address
Write
command register
track register
sector register
data register
Write
330009
drive status reg. drive command reg.
- Drive status register
Bit
Name Active Note
D7
not used
D6
not used
DS
not used
D4
not used
D3 Disk out H
Disk out status
D2 INT
H interrupt status
Dl
2HD/2DD- H high density
DO DCHG H
disk charge status
Remarks
INT bit will be automatically reset when the
CPU reads the Drive status register.
7-9
www.icdia.co.uk