Ciprico Rimfire 3880, User Manual

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User’s Guide 21020285 D
Chapter 6 Target Mode Pass-through Commands
Overview of Target Mode Page 6 - 3
Overview of
Target Mode Of course, if you are familiar with the SCSI specification, you already know
that operation over the SCSI bus takes place between two parties: the initiator
of the operation, and the target of the operation. In the SCSI specification,
protocol for each party is exactly detailed. A target has certain responsibilities
in a transaction, and an initiator has other specific obligations.
Most of this manual has been devoted to describing how the Rimfire 3880 can
be used as an initiator on the SCSI bus. This chapter explains how the RF3880
can be used as a SCSI target. It explains a mode of operation for the adapter
that is called Target Mode.
What is Target
Mode?
The Ciprico implementation of Target Mode on the RF3880 offers flexibility
to the person writing a driver for it. The adapter actually makes very few
independent decisions. Instead, when acting as a target, transaction information
is passed to the Host, and the Host frames the response that the adapter will
make as the target. The driver that handles Host business must be written to
follow the SCSI specification as well as the Ciprico protocol presented in this
chapter.
When Target Mode is enabled, the adapter will accept selections from initiators
and initiate reselections. It will also continue to function as an initiator,
selecting targets at the request of the Host, and accepting reselections.
Figure 18 RF3880 in Target Mode