User’s Guide 21020285 D
Chapter 7 Board-control Commands
Target Mode Enable (0AH) Page 7 - 27
Target Mode Enable (0AH)With this command you instruct the RF3880 to begin accepting selection from
initiators on the SCSI bus. The adapter will still operate as an initiator, but after
this command has been issued, it will also operate as a target, until a Target
Mode Disable command is sent or a SCSI bus reset occurs.
Command
Format
The Parameter Block format for th e Target Mode Enable command looks like
this:
Note
If you send a Target
Mode Response
command to the RF3880
before you have enabled
it to act in Target Mode
with the Target Mode
Enable command, the
Response command will
be terminated with an
error code. If you send
the RF3880 an Enable
command while it is
already enabled, the
second Enable command
will terminate with an
error code.
Description of
Fields
Each of the fields used by the Target Mode Enable command are explained in
the following section:
Command Identifier
The Command Identifier is used to identify the Status Block associated wi th a
Parameter Block. The adapter also writes this value into the Command
Identifier area of the Target Selection Data Structure. It must be a unique value.
Adapter ID
This field must contain an FFH to indicate that it is an adapter command.
Address Modifier
This is the value that the adapter is to drive onto the VMEbus Address Modifie r
lines when selecting the memory address of the Target Selection Data Structur e.
Pointer to the Target Selection Data Structure
This field contains the address of the area to be used by the adapter to create a
Target Selection Data Structure after being selected by an initiator.
Address
Offset Byte Memory Address
Offset + 0Offset + 1Offset + 2Offset + 3
00H Command Identifier
04H Reserved Reserved Addr Mod Adapter ID = FFH
08H Pointer to Target Selec ti o n Data Structure
0CH Reserved Selection Interrupt
10H Command = 0AH Test Flags Reserved
14H Reserved
18H Reserved
Table 83: Target Mode Enable Parameter Bl ock