Chapter 7 Board-control Commands
Target Mode Enable (0AH) | Page 7 - 27 |
Target Mode Enable (0AH)
Command
Format
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.
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.
The Parameter Block format for the Target Mode Enable command looks like this:
Address |
|
| Byte Memory Address |
|
| ||
Offset | Offset + 0 |
| Offset + 1 |
| Offset + 2 |
| Offset + 3 |
|
|
|
| ||||
00H |
|
| Command Identifier |
|
| ||
|
|
|
|
|
|
| |
04H | Reserved |
| Reserved |
| Addr Mod |
| Adapter ID = FFH |
|
|
|
|
| |||
08H | Pointer to Target Selection Data Structure | ||||||
|
|
|
|
|
| ||
0CH | Reserved |
|
| Selection Interrupt | |||
|
|
|
|
|
|
| |
10H | Command = 0AH |
| Test Flags |
|
| Reserved | |
|
|
|
|
|
|
|
|
14H |
|
|
| Reserved |
|
| |
18H |
|
|
| Reserved |
|
| |
Table 83: Target Mode Enable Parameter Block
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 with 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 Modifier lines when selecting the memory address of the Target Selection Data Structure.
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.
User’s Guide | 21020285 D |
