LSI53CF92A LSI, LSI53CF92A Datasheet - Page 38

• Manufacturer Part Number: LSI53CF92A
• Manufacturer: LSI

Specifications of LSI53CF92A

• Lead Free Status / RoHS Status: Not Compliant

2.8.1 SCSI Low-Level Programming
2.8.2 SCAM Operations
2.8.2.1 Arbitration With or Without an ID
2-18
The LSI53CF92A design provides SCAM capability with a generic
low-level SCSI programming mode. Low-level access to the SCSI bus is
controlled by the Low Level bit,
bit 0. When the Low Level bit is set, all SCSI bus sequences are
performed using software control. Arbitration may be performed purely in
software or by using the ARB bit,
bit 1. See
operation, no relational restrictions exist between SCSI signals; data bits
may be driven without respect to the I/O control line, and there is no
distinction between target/initiator signals.
The following categories describe the different SCAM operations:
Arbitration with or without an ID is possible through low-level control by
utilizing the SCSI Output Data Latch and the ARB bit,
(SCONTROL)
SCSI Output Data Latch (SODL)
direct bit-mapped fashion. During arbitration, legal values for the
SCSI Output Data Latch (SODL)
0x20, 0x40, 0x80}. Arbitration without an ID is accomplished by setting the
SODL to {0x00} prior to the start of arbitration. The following steps should
be performed by software to arbitrate for the SCSI bus in low-level mode:
Step 1. Set the Low Level bit in the SCSI Control register.
Step 2. Write bit-mapped ID (normal arbitration) or 00 (no ID) to the
Functional Description
Copyright © 1995–2002 by LSI Logic Corporation. All rights reserved.
Section 2.8.2.1, “Arbitration With or Without an ID”
Section 2.8.2.2, “SCAM Selection”
Section 2.8.2.3, “Response to SCAM Selection”
Section 2.8.2.4, “Response to Normal Selection”
Section 2.8.2.5, “SCAM Protocol and Transfer Cycles”
Section 2.8.2.6, “Limitations”
SCSI Output Data Latch (SODL)
Section 2.8.2, “SCAM
register, bit 1. During arbitration, the contents of the
Operations,”, for details. During low-level
SCSI Control (SCONTROL)
are asserted onto the SCSI bus in a
are {0x01, 0x02, 0x04, 0x08, 0x10,
SCSI Control (SCONTROL)
register.
SCSI Control
register,
register,