LSISASX12 LSI, LSISASX12 Datasheet - Page 52

• Manufacturer Part Number: LSISASX12
• Manufacturer: LSI

Specifications of LSISASX12

• Lead Free Status / Rohs Status: Not Compliant

2.7.1
2.7.2
2-30
Doorbell Interface
I
2
C Addressing and Transfer Modes
The STP EMB doorbell messaging interface provides a communication
channel between the STP target and the SEP. The LSISASx12 STP sets
the various bits in the STP-SEP Doorbell registers to send commands to
the SEP. The STP-SEP Doorbells are the interrupt sources.
The SEP sets bits in the SEP-STP Doorbell register, which are inputs to
the LSISASx12 STP.
The STP is accessed through the I
slave behaves in a similar manner to industry standard serial EEPROM
devices. The first byte on the bus following a start condition provides the
control byte. The control byte consists of a 4-bit device type code that is
set to 0b1010. Following the device type code is a 3-bit device address
(A2, A1, A0). Bit A2 is hard-coded to a value of 0, and ISTWI_ADDR[1:0]
provide bit A1 and bit A0 respectively. The last bit of the control byte
indicates if the operation is a read or write. When set to one (1), the
operation is a read. When cleared to zero (0), the operation is a write.
Figure 2.6
modes. The I
transfers or block transfers. The most-significant bit of the Address
Pointer Hi byte (BLK) selects the transfer mode of the current operation.
Clearing the BLK bit selects the byte transfer method. Setting the BLK
bit selects the block transfer method. For block transfers, the third data
byte provides the byte count. A byte count of zero indicates a 256 byte
transfer.
Functional Description
Copyright © 2004, 2005 by LSI Logic Corporation. All rights reserved.
Generating CRC for outbound SATA FISes.
Generating and transmitting OAFs when a SATA FIS is ready to be
sent to the STP Initiator.
Responding to PMREQ_S and PMREQ_P primitives with PMNAK.
provides an illustration of the slave addressing and transfer
2
C can transfer data to/from the I
2
C. The device addressing for the I
2
C slave using byte
2
C