Avago Technologies LSI53C320 - Manual (Page 24)

2-6 Functional Descriptions
Version 2.2 Copyright © 2003 by LSI Logic Corporation. All rights reserved.
Figure 2.3 Example of Precompensation
2.2.1.3 Packetized Transfers
Packetized transfers are also referred to as information unit transfers.
They reduce overhead on the SCSI bus by merging several of the SCSI
bus phases.
2.2.1.4 Skew Compensation
The LSI53C320 provides a method to account for and control system
skew between the clock and data signals. Skew compensation is only
available when the device operates in the Ultra320 SCSI mode. The
initiator-target pair uses the training sequences in the SPI-4 draft
standard to determine the skew compensation. The LSI53C320 passes
the training patterns between the initiator and target. The LSI53C320
stores the adjustment parameters and recalls them on subsequent
connections with the given device pair (nexus).
Normal Drive Strength
Normal Drive Strength Reduced Drive Strength
a. Drivers with Precompensation Disabled
b. Drivers with Precompensation Enabled