40
HA2 /
HA1
61
64
I
S
ATA Address
(ATAPI Mode):
The host uses the 3-bit ATA address to
select an ATAPI control command block register or data port.
HA0 /
48M
62
I
S
ATA Address 0 (ATAPI Mode):
The host uses the 3-bit ATA address to
select
an ATAPI control command block register or data port.
48MHz USB Reference Clock (USB Mode):
If bit USBCKSEL (0A9h.2) = 1,
48M is used as the USB reference clock input, and a 48MHz clock signal
must be input to 48M. If USBCKSEL = 0, the internal system clock
(controlled by bits PLLCO1
[2FEh 2FDh]) is used, and 48M must be
grounded.
IOCS16#
66
O
OD
ATA I/O Chip Select 16 (ATAPI Mode):
For PIO transfer, IOCS16#
indicates to the host system that the 16-bit data port has been addressed
and the chip is prepared to send or receive a 16-bit data word.
CS1FX# /
USBD–
59
I
S
ATA Chip Select 1 (ATAPI Mode):
The host uses this signal to select the
ATAPI command block registers for access.
USB Differential Serial Data
Negative (USB Mode)
CS3FX# /
SCSICLK /
USBD+
58
I
S
ATA Chip Select 3 (ATAPI Mode):
The host uses this signal to select the
ATAPI control block registers for access.
SCSI Reference Clock (SCSI DMA Mode):
If bit SCSICLKS (07Bh.6) = 0,
this signal is used as the SCSI DMA reference clock (40MHz is
recommended). If SCSICLKS = 1, the internal CD-Decoder system clock
(controlled by bits PLLCO1
[2FEh 2FDh]) is used, and this signal must
be grounded.
USB Differential Serial Data
Positive (USB Mode)
HDRQ /
DREQ
73
O
TS
ATA DMA Request (ATAPI Mode):
This signal will be asserted for DMA
data transfer when the chip is ready to transfer data to or from the host.
This signal is used in a handshake manner with DMACK#.
I
SCSI DMA Request (SCSI DMA Mode):
The SCSI protocol controller uses
DREQ to request data transfer with the OTI-9797.
DMACK# /
DACK#
69
I
PU
ATA DMA Acknowledge (ATAPI Mode):
This signal is used by the host to
respond to HDRQ.
O
SCSI DMA Acknowledge (SCSI DMA Mode):
The OTI-9797 uses DACK#
to acknowledge it is ready for data transfer.
Pin Name
Pin #
Type
Description