LSI Logic Confidential
14-2
Bitstream I/O (Storage) Port
Copyright © 2001, 2002 by LSI Logic Corporation. All rights reserved.
14.1 ATAPI Interface
The ATAP interface supports the following operations:
•
Register read
•
Register write
•
DMA read
•
DMA write
The Register read and write operations are used to configure a set of
ATAPI device registers. The DMA read and write operations are needed
for transferring long sector data.
The ATAPI read and write cycles are described in
. The ATAPI
register address is defined by the output pins CS0, CS1, DA2, DA1, and
DA0, where CS0 is the most significant bit.
14.1.1 Read Cycle
The ATAPI read cycle starts when the ATAPI Interface receives the
ATAPI_RD command from the host. The ATAPI Interface subsequently
puts the register address on the address bus and asserts the
ATAPI_DIOR signal t1 time later. The 16-bit data (AtapiIOCS16 signal is
always low) from the ATAPI device is latched by the ATAPI Interface
during the rising edge of the ATAPI_DIOR signal.